Feed ramp issues on new POF upper ... need HELP!!


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1858
February 16, 2009, 02:15 AM
I took my new POF upper to the range today and what a disaster it was!! Yesterday I measured the chamber with a Stoney Point OAL gauge and loaded up some Winchester brass that had been full-sized and trimmed to length (1.750"). I used a Hornady 75gr BTHP bullet and couldn't seat it anywhere close to the "optimum" length of 0.020" - 0.040" off the lands due to the interior dimensions of the Bushmaster magazines. I ended up with a COL of about 2.270" which just fits in the magazine. Basically, I had to seat the bullet about 0.090" off the lands (long POF throat I guess). Anyway, now to the problem ... I only managed to shoot five rounds due to the fact that almost every round jammed during the chambering process. Take a look at the photo of the POF chamber below and compare it to the chamber of my DPMS upper (also below). The DPMS has two distinct feed ramps inline with each position that a round might occupy in the magazine. The POF doesn't have two distinct feed ramps. WHAT AM I MISSING HERE!! Is the POF upper supposed to use single stack magazines, a particular type of bullet, a specific COL? I'm really at a loss and am hoping for some ideas before I call POF. In case you're wondering, the lower that I was using is a Bushmaster, the magazines are Bushmaster 10 round versions with "new", gray no-tilt followers. The magazines work fine when used with a Bushmaster lower and DPMS upper. I'd REALLY appreciate some help here. On the bright side, the five shots that I managed to get off grouped well at 50 yards and the Troy sights are excellent.

POF chamber and feedramp:

http://128.171.62.162/hawthorn-engineering/thr/POF.jpg

DPMS chamber and feedramps:

http://128.171.62.162/hawthorn-engineering/thr/DPMS.jpg

:(

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Duelist
February 16, 2009, 08:08 AM
Use factory ammo.

briansmithwins
February 16, 2009, 09:32 AM
I agree to use factory ammo for starters.

However, it really looks like POF skipped the step where feed ramps are machined into the extension. Have you contacted POF yet? BSW

taliv
February 16, 2009, 10:02 AM
dude, that's messed up. i can't tell from the pic, but does it even have a feed ramp? try unhinging the lower and taking a pic from the bottom

rbernie
February 16, 2009, 11:18 AM
Looks like somebody forgot to machine the feedramps.

gvnwst
February 16, 2009, 11:19 AM
The feedramps are there, just not machined enough. I don't know why though...?

Try some factory ammo, mine has been flawless with any i have put through it.

1858
February 16, 2009, 01:21 PM
First, thanks for your comments. I called POF this morning and they told me to ship it back to them with a note. :mad: When I asked their tech support guy if their upper can only handle factory ammunition he said that it should be fine with reloads but he basically implied that my reloads are probably "defective". Tell that to my DPMS that has devoured hundreds of them without any problems.

dude, that's messed up. i can't tell from the pic, but does it even have a feed ramp? try unhinging the lower and taking a pic from the bottom

Looks like somebody forgot to machine the feedramps.

However, it really looks like POF skipped the step where feed ramps are machined into the extension. Have you contacted POF yet? BSW

The feedramps are there, just not machined enough.

Four observations implying that the feedramps aren't machined enough ... BUT .... if you take a look at the DPMS image, imagine machining out the center "divider" between the two feedramps ... that's what POF has done. In other words, their feedramp is just one scalloped region that's as deep as the DPMS feedramps. The POF feedramp allows the round to over rotate AWAY from the centerline of the chamber. What was happening yesterday was the bolt would strip a round off the magazine, the bullet would hit the feedramp and continue rotating so that the case head would move AWAY from the bolt head rather than seat in the bolt head, and then the round would jam in the chamber because it's not going in straight.

I will try factory reloads in a couple of weeks. I sent an email to POF with the two photos in this thread so hopefully they'll have a better idea BEFORE I have to mail this POS (I mean POF) back to them.

Thanks for the comments/observations/thoughts.

:)

bonedust
February 16, 2009, 03:31 PM
every company has a hiccup here and there. i have yet to come across any company in this industry that doesnt serve up a turd now and again. POF is great product imo, and will certainly make the rifle right.

i would also try factory ammo before returning the gun. juts my 2cents.

Hoppy590
February 16, 2009, 03:52 PM
those ramps are epic failures.

if those were a mistake, its a big one and some one should have caught it. if they are designed that way. i cant see them being effective.

1858
February 16, 2009, 10:24 PM
So I tried feeding some factory ammunition today loaded in GI issue magazines with Bushmaster no-tilt followers. The ammunition is Remington something or other that I had lying around in magazines (box long gone). I always feel "nervous" letting the slide strip off a live round at home in case of a slam fire ... the local police would love that! Anyway, it didn't work either and the round got jammed half way in the chamber. Here are some more photos. In the first photo, you can see that the round isn't aligned with the bolt and the head of the case isn't seated against the bolt face properly.

http://128.171.62.162/hawthorn-engineering/thr/POF_1.jpg


http://128.171.62.162/hawthorn-engineering/thr/POF_2.jpg


http://128.171.62.162/hawthorn-engineering/thr/Rem.jpg

I'm going to call my local gun shop where I bought the upper and see if they has any ideas before I send it back to POF. They had four come in so maybe he'll do a swap but I doubt it. At this point I'm starting to think it's defective rather than being my ammunition, magazines etc. One last thing to check is the ejector/extractor or whatever it's called.

:(

flynlr
February 17, 2009, 02:59 AM
while I am sure you have a problem with that upper and you confirmed it with factory ammo. the MAX OAL seen in all the reloading manuals I have is 2.260
I ended up with a COL of about 2.270" which just fits in the magazine

1858
February 17, 2009, 03:33 AM
while I am sure you have a problem with that upper and you confirmed it with factory ammo. the MAX OAL seen in all the reloading manuals I have is 2.260

I've fired many, many rounds (77gr SMK HPBT) through my DPMS upper with a COL of 2.270" (0.025" off the lands) without a single feeding problem. Basically, if the round will fit in the magazine and you've measured the chamber to determine the max COL then 2.270 isn't a problem.

:)

Target in sight
February 18, 2009, 06:37 PM
I recently had some issues with my POF in which I believe the issue to be in the extractor. While searching to increase my knowledge I came across this post. I also found another post that seems to describe your issue.

http://wintersoldier2008.typepad.com/summer_patriot_winter_sol/2008/06/reliability-and-functioning-issues-with-the-ar-style-rifle.html

You will find it about two thirds of the way down in the article. I hope this helps since my upper is now on its way back for the second time from POF. I do have to say they have been very responsive to my problem, but I do hope the issue is finally resolved.

I notice on a lot of sites people never post back after I assume they resolve their issues. Please post back with your success/failure.

1858
February 18, 2009, 09:36 PM
Target in sight, thanks for the link ... very interesting and it may well help me to resolve this issue.

I called the gun shop on Monday that I ordered the POF upper from and he told me that another upper from the same lot has/had the same problem. I don't know if the other two from the same order have been picked up or fired yet. He must have sold it to a friend since he said he was at the range trying to help him with it this past weekend. He claimed that after 20 or so problematic feeds followed by firing, the upper became 100% reliable. When I called him a second time he was starting to get annoyed and basically told me that it's between me and POF. Not the kind of response that I was expecting since he was the one that recommended POF in the first place. Anyway, I called POF twice and they offered no explanation for the different feedramps other than "that's how we do it". I will add that I no longer think that the feedramps are the problem based on the 50 or so attempts to chamber a round using dummy rounds. I seated a couple of 55gr bullets in cases that had been trimmed to the correct length. I didn't use any powder or a primer and must have cycled the action more than 50 times. I found that with one round in the magazine I had a higher success rate than with two which failed to chamber 99% of the time. I'm now convinced that it's something else and if I can swap the bolt from my other AR I'll try that tonight. I don't know if the bolts are interchangeable but if they are that will certainly help the troubleshooting process. I did try a different charging handle just in case but that didn't help.

I'm still confused about the twist rate of the barrel. Chris at POF said that it's 1:8 but I'm sure that it's 1:9 based on the rotation of a cleaning rod and patch. My DPMS upper which has 1:8 stamped on the barrel checks out at that twist rate with a cleaning rod and patch.

Well, this hasn't turned out to be a great experience thus far. It's a pity since the POF looks to be very well made and just reeks of quality. I'll report back once I resolve this issue. I'm trying to avoid sending the upper back, but if I can't make any progress I'll have to ship it to POF.

:)

gvnwst
February 18, 2009, 09:41 PM
If you are using just the bolt, it should work, POF says they are the same....they are. Firing pin and everything is also the same.

1858
February 18, 2009, 09:49 PM
gvnwst, thanks ... I don't have the upper in front of me but I suspected that the bolts would be interchangeable ... the carriers are a different story of course. Changing bolts could help me to figure out if it's the extractor/ejector or bolt head that's causing the problem. The chambering process beat the crap out of the two dummy rounds that I loaded so I'll make up a couple more.

:)

1858
February 19, 2009, 05:05 AM
OK ... I'm making some progress so thanks again to Target in sight for the link which persuaded me to continue trying to figure it out. After switching the extractor, checking the ejector, changing the cam guide (or whatever it's called), and finally changing the whole bolt, I can say without a doubt that it's the POF BOLT that's causing the feeding problems. The DPMS bolt has gas rings on it but it fit in the POF carrier. I tried three magazines loaded with four dummy rounds and despite being badly beaten up, all of the rounds chambered effortlessly multiple times and were ejected without any problems. As soon as I installed the original POF bolt, the action would jam immediately when trying to chamber a round. I don't know what it is about the bolt that's causing the problem but it's 100% the bolt and NOT the feedramps. The ejector looks ok and doesn't appear to be stuck. The extractor is a bit stiff compared to the DPMS extractor but swapping them out didn't help so it probably isn't an extractor problem. The link posted by TiS mentions honing the bolt face to make sure that there aren't any burrs or other irregularities. This seems to be the next logical step before calling up POF and requesting a new bolt. Other than that, I'm not sure what the problem could be with the bolt.

Anyway, my apologies to POF for implying that their feedramps are rubbish ... I should have said that their bolts are rubbish as is their quality control and testing before sending their products out the door. :cuss:

:)

taliv
February 19, 2009, 09:03 AM
you forgot their customer support

rbernie
February 19, 2009, 11:12 AM
Anyway, my apologies to POF for implying that their feedramps are rubbish I would still maintain that their feedramps are rubbish, regardless of the fact that they INTEND for them to look that way.

But that's just me.

Walkalong
February 19, 2009, 12:07 PM
I am no expert by a long shot, but those feed ramps, or lack therof, on the POF don't look like anything I have seen on an AR or in any pics of AR feed ramps.

I looks quite different from this pic for sure.

http://www.thehighroad.org/attachment.php?attachmentid=93059&d=1235063232

jerkface11
February 19, 2009, 12:11 PM
But I thought gas piston AR's were uber reliable.

1858
February 19, 2009, 12:49 PM
But I thought gas piston AR's were uber reliable.

First off, I'm telling it EXACTLY like it is for good or bad ... that's always been my approach in life and on this board. With truth comes understanding and honest assessments of a system enable others to make informed choices. I will say that I categorically DID NOT make an informed choice. However, knowing what I know now I would STILL buy a POF upper for a number of reasons. First, because I don't think that the POF feed ramps are inherently unreliable. In fact, I've spent so much time focusing on the feed ramps and their interaction with the round as it's chambering that I'm now convinced that the design is solid. Second, the bolt problem isn't unique to the gas piston system ... in fact it has nothing to do with it and ANY AR platform could have the same issue. Third, I still like the idea of an action that runs cooler and cleaner and for that, a gas piston system is needed. Finally, the upper is EXTREMELY well made in terms of the machining, fit, finish, quality of materials etc.

I did have a thought last night about the bolt, I'm going to install the POF bolt in the DPMS upper and see if it cycles without any issues. That might shed more light on what's going on.

Walkalong, thanks for the photos of the M4 and "regular" feed ramps. This thread may well help others who are thinking about buying an upper.

I don't know how others here feel but I become more "connected" to a tool or piece of equipment when I work on it. Must be like a doctor/patient type of thing. I've cycled the action so many times on this upper, removed the bolt about 30 times, switched stuff around, cleaned, inspected, cleaned again ... we've formed quite a bond and it's done wonders for my AR handling skills.

:)

jerkface11
February 19, 2009, 01:09 PM
Yup the problem obviously has nothing to do with nonstandard parts. Oh wait it isn't a standard bolt is it?

1858
February 19, 2009, 01:18 PM
Yup the problem obviously has nothing to do with nonstandard parts. Oh wait it isn't a standard bolt is it?

Yes, it's a standard bolt but without the gas rings which could be added/removed if necessary since the annular gas ring groove is there. As I mentioned above, a DPMS bolt in the POF bolt carrier worked perfectly.

:)

1858
February 19, 2009, 05:16 PM
Notice anything different comparing the POF bolt (silver) to the DPMS bolt (black)? The arrows may help.

I installed the POF bolt in the DPMS carrier (using the DPMS upper) and the first round fed ok, the second one jammed, but after that, 25 rounds fed without a hitch. I don't know for sure that the problem is the cam (or whatever it's called) but I'm in the process of honing the POF bolt where the cam resides.

http://128.171.62.162/hawthorn-engineering/thr/bolt1.jpg

http://128.171.62.162/hawthorn-engineering/thr/bolt2.jpg

:)

gvnwst
February 19, 2009, 09:11 PM
Okay, something is messed up with the bolt and or cam pin. Here is a pic (welll, 2) of my POF bolt, with the pin in. Sorry, one is not the greatest, but the camera was free, and better than having to use film...:
http://i362.photobucket.com/albums/oo64/gvnwst/100_2062.jpg
http://i362.photobucket.com/albums/oo64/gvnwst/100_2063.jpg

1858
February 19, 2009, 09:27 PM
gvnwst, thanks for posting the photos. After spending a while honing the cam pin hole, so that the pin rotates freely and now falls all the way through the hole, I reassembled the bolt and carrier with high hopes that this would be it. NAHHHHH!! :banghead: The action jammed again on the even numbered rounds (in the magazine). So I finally gave up, removed the gas rings from the DPMS bolt and assembled the POF bolt/carrier and upper with the DPMS bolt. Everything's fine in that configuration with dummy rounds flying around the room at will. I installed the POF bolt in the DPMS upper where it's about 80% reliable so the POF bolt is basically EVIL :evil: I'm going to call POF tomorrow to ask them to send me a new bolt but they probably won't agree to that. I looked online to see if I could buy a bolt but DPMS, Stag Arms, Midway, PRI are all sold out!!

What function do the bolt gas rings serve on "regular" uppers? They're kind of like piston rings but what exactly is there purpose?

Anyway, short of an epiphany, act of God, or other divine intervention, this is it for me. I don't have the time or the energy to figure out what the heck is wrong with the POF bolt.

:)

gvnwst
February 19, 2009, 09:34 PM
You know how DI works, right? Basically it shoves the gas into the BCG, and pushes on that part of the bolt. Hence the gas rings. They are to seal it, the POF, not having that gas, doesn't need them.

rino451
February 19, 2009, 09:53 PM
Doesn't need them but I bet that the lack of them allows the bolt to rock w/i the carrier causing the bolt case interface to be off kilter.

taliv
February 19, 2009, 10:12 PM
uhh, dude, i hate to tell you this, but the cam pin is NOT supposed to fall all the way through that hole. it's closed on purpose to prevent our boys in uniform from installing the bolt rotated 180* which would eject the spent case left into the side of the receiver instead of right out the aptly named ejection port

if you've filed that away, that's not good

1858
February 20, 2009, 12:12 AM
if you've filed that away, that's not good

Why's that taliv ... it's my AR and I KNOW which way the bolt goes in the carrier so do you really think that I need to have an indexed cam pin hole in the bolt? :confused: I know why the cam pin hole is indexed but thanks for your concern.

Doesn't need them but I bet that the lack of them allows the bolt to rock w/i the carrier causing the bolt case interface to be off kilter.

Good thought process but the DPMS bolt WITHOUT the gas rings is working just fine in the POF carrier.

You know how DI works, right? Basically it shoves the gas into the BCG, and pushes on that part of the bolt. Hence the gas rings. They are to seal it, the POF, not having that gas, doesn't need them.

Yes, I know how dgi works but the point of my question is whether or not the POF bolt without the gas rings will function properly (at least for a while) in the DPMS upper. The gas doesn't act on the bolt directly, it acts on the bolt carrier KEY which is in top of the carrier so I'm wondering if the gas rings are there to prevent blow-by so as to reduce the amount of fouling that gets into the bolt. In other words, the bolt may need to be cleaned more often but it'll still work ok in a pinch. The pinch here is that I need to order new gas rings which aren't available at the moment.

:)

charlesb_la
February 20, 2009, 10:59 AM
Originally Posted by 1858
The gas doesn't act on the bolt directly, it acts on the bolt carrier KEY which is in top of the carrier so I'm wondering if the gas rings are there to prevent blow-by so as to reduce the amount of fouling that gets into the bolt.


You are incorrect, the gas carrier key is only there to conduct the expanding gasses into the bolt carrier. Inside the bolt carrier the gas forces the bolt carrier back AND the bolt forward. This pushing back on the bolt carrier cams the bolt open via the cam pin. The gas rings are required for operation. Without the gas rings the gas will leak by and not exert enough force on the carrier.

taliv
February 20, 2009, 11:08 AM
I know why the cam pin hole is indexed but thanks for your concern.

then why did you file it off?

1858
February 20, 2009, 02:28 PM
You are incorrect, the gas carrier key is only there to conduct the expanding gasses into the bolt carrier. Inside the bolt carrier the gas forces the bolt carrier back AND the bolt forward. This pushing back on the bolt carrier cams the bolt open via the cam pin. The gas rings are required for operation. Without the gas rings the gas will leak by and not exert enough force on the carrier.

Thanks, I appreciate the education/clarification ...that's what this board is all about for me. I've learned an incredible amount here. After reading your post, I took the DPMS bolt/carrier apart and using a flashlight I can see the port in the carrier beneath the carrier key that I didn't know was there. I straightened out the gas rings from the DPMS bolt and installed them on the POF bolt. Now I have two functioning uppers but it's been a PITA to get to this point. On the bright side I feel that I know more about the AR system than I did last week.

taliv , I wanted rule out as many variables as possible in my failed attempts to figure out why the POF bolt won't work in the POF upper, but will work in the DPMS upper. Allowing the cam pin to move up/down without any resistance was part of that process. Since I'm not worried about the chance of installing the cam pin 180 degrees off, I didn't (and don't) have a problem with what I did. Now, if you know of another reason why that was a bad idea (that can easily be corrected with a new bolt), then PLEASE let me know. I've already proven my spectacular lack of knowledge regarding the AR system so another erroneous assumption on my part is neither here nor there. :D

Many, many thanks to everyone for your input and help. I will be calling POF today to ask for a new bolt and to find out if they've had a bunch of bolt-related issues recently. I don't know if they manufacturer their own bolts in-house or if they order them from another vendor but I'll ask about that too.

:)

1858
February 20, 2009, 03:18 PM
I spoke to the guys at POF this morning and they have had some bolt-related issues. Their bolts are made by Stag Arms but in order to have POF replace the bolt, they need the upper back. I mentioned that I could buy a new bolt for the cost of the shipping and they offered to cover the cost of shipping back to them. However, since the POF bolt is just a regular bolt (with some chrome on it), I don't see a problem keeping the DPMS bolt in the POF carrier and the POF bolt in the DPMS carrier so that's what I'm going to do.

Thanks again for all of your help ... that should be it ... and I hope I won't have to bore you any more with my trials and tribulations.

:)

charlesb_la
February 20, 2009, 04:35 PM
Glad to hear that POF is standing behind their product. I've had one for a couple of years and it had never had a stoppage of any kind. Every manufacturer has problems so don't let it get you down on your rifle, when you get it straightened out it will run and run.

As far as the education I think most shooters think that dgi works like a hose spraying into a cup, until they delve deeper into the system. I know I did.

Enjoy the rifle, it's a nice one.

1858
February 23, 2009, 02:08 PM
What a difference a week (and a DPMS bolt) makes!!! :D I put 25 reloads through the POF upper on Saturday without a single issue. The bolt went into battery every time and all the cases ejected without drama ... I KNOW I'm going to love this upper. I got the Troy sights dialed in at 50 yards (1" grouping) and then got them very close at 100 yards with perfect windage but maybe an inch or two high before the end of the day. The ejected cases end up three to four feet forward and to the right which makes brass retrieval a lot easier.

Every manufacturer has problems so don't let it get you down on your rifle, when you get it straightened out it will run and run.

Very true ... it's how a company DEALS with those problems that makes ALL the difference.

As far as the education I think most shooters think that dgi works like a hose spraying into a cup, until they delve deeper into the system. I know I did.

Yep, that's what I thought but now I know better ... thanks. :)

I bought a one-piece gas ring yesterday so I'll put that on the POF bolt and run it next weekend in the DPMS upper to see if everything works fine. If it does, then that's where it'll stay.

:)

1858
February 23, 2009, 05:23 PM
I need a quick reality check here ... headspacing isn't an issue with the AR platform right? In other words, any bolt should be fine in any carrier with any barrel ... is that correct? The reason I'm asking is that the DPMS bolt is working perfectly in the POF carrier. IF the POF (Stag Arms) bolt works perfectly in the DPMS carrier I'd like to leave them where they are ... that's if headspacing is not an issue.

My current "theory" as to why the POF (Stag Arms) bolt doesn't work in the POF carrier is based on the Gaussian distribution of error found in ALL machined parts. It's my contention that the POF (Stag Arms) bolt is at one end of the curve (mean minus 3 standard deviations) and the POF carrier is at the other end of the curve (mean plus 3 standard deviations). The DPMS bolt and carrier are both in the middle of the error curve so the POF bolt works with the DPMS carrier (3 SD apart) and the DPMS bolt works with the POF carrier (3 SD apart), but the POF bolt doesn't work with the POF carrier (6 SD apart). Got it? :D

Thanks.

:)

charlesb_la
February 23, 2009, 05:56 PM
Well maybe. The headspace is set when the barrel is installed into the barrel extension. If both barrels were installed correctly and both bolts are in spec it shouldn't matter. It would also depend on how much wear on the bolts. If they were both relatively new the it shouldn't be a problem.

The safest way would be to drop by a local gunshop and test them both with GO/NO GO gauges.

When I went through basic and we were cleaning the bolts we threw the whole platoons' bolts in one bucket of cleaning solution and then everyone just pulled one out and used it. No Kabooms but with your POF being new you might want to run the gauges to be sure.

Oh and I'm not to sure about Gaussian distribution of error, I just call it tolerance stacking.:D

charlesb_la
February 23, 2009, 06:02 PM
Another thing I just thought of. It could be a tolerance stacking :D issue with the coating that POF applies to the upper and the bolt. If it was just a little too thick on each it could add up to enough to cause problems even though each was in spec before coating. This could explain why the POF bolt works in the non coated DPMS upper and the DPMS bolt works in the POF upper. If this is the case it may wear in over time if it's just a hair to thick.

1858
February 23, 2009, 06:09 PM
The DPMS upper is fairly new too with about 100 rounds through it so I should be ok if I understand you correctly? That's an excellent point about the coating on the POF bolt and carrier and I had thought about that as being an explanation as to why it took 20 to 30 rounds for the other POF upper to feed reliably. You would think that POF would be aware of that "wearing in" issue if it takes that many rounds for the "high spots" on the coating to wear away ... anyway, just a guess on both our parts but certainly plausible. I don't know if Stag or POF coats the Stag bolts ... ultimately it doesn't matter.

I'm going to order a POF upper in .308 in the next couple of months so I hope that I don't have the same problem since I don't have a spare .308 upper to swap parts with. :eek:

Thanks.
:)

charlesb_la
February 23, 2009, 08:52 PM
Just be careful. The only thing that bothers me is that the POF is new and you haven't really established a track record with it so you can't be sure it was headspaced correctly in the first place. It's rare but does happen.

If you don't check the headspace be sure to check your fired brass for any signs of too much/ or too little headspace.

You could also post on the POF industry forum on ar15.com for responses from more knowledgable people than me.

http://www.ar15.com/forums/forum.html?b=2&f=206

Target in sight
March 4, 2009, 04:38 PM
Well, since earlier I had made the comment that a lot of people don't post their final outcome to problems I decided I had better report mine. My POF upper came back from the factory again after I was having issues with jamming and tiny dents on the spent rounds. I then conducted a test with six different brands of ammo. It turns out the PMC Bronze was the culprit. Maybe just a particular batch, but the gun would fill with unburned powder after each shot until it accumulated enough to jam the loading round. The dents.. unburned powder that sandwiched between the shell case and the chamber wall during obturation when fired. In my test I used PMC Bronze, American Eagle, Norinco, Wolf, Centurion, and some old 1980 PMC. Only the Bronze Box PMC gave me trouble. A little research showed that PMC changed to a new powder that they designate PMC2222. I am shooting an sbr so I am sure it has to with the powder/primer combination of the load and barrel length. I don't know about others, but Greg at POF was great about trying to resolve my problem I relayed my test results to him which he said would be passed on. I was left with a good feeling from POF. Good thing, you don't want to have a bad taste in your mouth every time you pick up the high $$$ toy. That kind of takes the fun away.
One more note. The PMC bronze fired fine in 16"plus barrels.

1858
March 9, 2009, 07:14 PM
Target in sight, good to hear that you resolved your issue. POF has been very good in terms of customer service/support. I managed to get through to Chris (and Greg) immediately on three occasions, and the one time I didn't, they called back within 10 minutes. They've followed up with emails and offered to pay the cost of shipping the upper back to them if necessary. All in all I'm very pleased with the support that they've given. I don't think it's their fault that the Stag Arms bolt is problematic. I will certainly be ordering another upper (in .308) from them in the near future.

As for my POF upper ... I installed the POF (Stag Arms) bolt in my DPMS carrier/upper and shot 35 reloads this weekend. I had four FTF events with the bolt not going into battery on two rounds but the last eight all chambered/fired without issue. In the end, I hope that I've worn the Stag Arms bolt sufficiently that it'll work in the POF carrier. I installed a new one-piece gas ring on the DPMS bolt and put it back in the DPMS carrier where it's going to stay. I removed the three gas rings from the Stag Arms bolt and that's back in the POF carrier.

:)

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