7mm Rem. Mag. Reloads - Please Help!

[The Mighty Beagle]

Okay, this is bizarre ...

Being more of a handgunner, I have reloaded my own ammo for years, but am just getting started with rifle reloading for a recently acquired (used) Remington 700 ADL.

I cleaned and adjusted my Hornady 7mm dies and, using my Lock-n-Load progressive press, I cobbled together 5 rounds using 7828 powder and 160 gr. bullets. All the measurements via calipers were within Sierra manual specs., though sometimes just barely.

Here's the thing: re-sized, empty casings will fit in the chamber of the gun nicely, even loosely. Loaded rounds, which are in spec, fit in snugly, and allow the bolt to seemingly go fully forward ...

However, the bolt handle will not turn down without significant force applied to it. With some annoyance, I was able to shoot the rounds, which were not at all hot loads. I was afraid of tearing up my gun, so I stopped there. BTW, gun works flawlessly w/ factory ammo.

So what's my problem? I've got the stupid sizing die screwed down as far as possible. I've tried experimenting with o.a.l. of the cartridges to no avail. It's like my gun doesn't like the once-fired nickel Winchester casings, or it's like that 'belt' is getting out of spec. after one firing.

What do I do? There's no way in hell I can afford factory ammo only in this gun ....

 

[dakotasin]

nor should you ever shoot factory ammo if you don't have to!

first, i don't load nickel cases... they are just too difficult to get right in rifles.
it sounds like you are sizing too much. neck size only, seat the bullets long. the difficulty w/ closing the bolt... perhaps the cases need trimmed? you'll likely need to trim after the first firing, maybe even the 2nd, but after that not as frequently.

fwiw, i size all new brass and trim to length before the first firing, and after the 2nd firing. after that, i go by measurement.

i've had great success w/ rl-25, win cases, fed mag primer, and hornady 162's.

 

[The Mighty Beagle]

Thanks Dakota, I'll take your advice.

You know, I thought about just neck sizing too - but my dies say they are "full length", so I just went ahead and tried that. I'm not exactly sure how much to back the die out to just "neck size".

I forgot to mention, the resized cases have a bulge right above the belt. I'm thinking they had that before I ever resized them, because I remember hoping my sizing die would do something about it. What could have caused this bulge? I wouldn't think the original factory load would be that hot.

BTW, I never dreamed that one firing could make the casings too long - but I do have an RCBS trimmer so I'll try that too, on regular brass casings.

Thanks!

 

[dakotasin]

i just picked up a 300 wsm not long ago, and got a couple boxes of ammo to have some fireformed reloadable brass in short order... after a single firing, the cases are so long that i can get the bolt to the half position, and that's all (now my saga searching for a trim plate is on...and am having a hard time, too).

you can neck size w/ the fl dies... just screw the die out. what i do is take a fired case, and size it. when it comes out, look for the marks on the neck to see where the sizing stopped. i size roughly 2/3 of the neck. the first time or two you do this, you are likely to sacrifice several cases getting it right. conversely, you can start w/ the die backed out a long ways, size, adjust, size, adjust until it is right. going from memory here, but i believe my dies (rcbs in a rockchucker) are about a dime's width from touching the shellholder when the handle is all the way down.

if you are still unsure, take a magic marker, color the entire neck and shoulder, then run it thru the sizer. should show up nicely what is being done when you pull the handle.

despite there being a belt, the 7 mag should be headspaced from the shoulder - thus if you are full length sizing as much as it sounds like, you are creating a little more space than there needs to be. probably detrimental to accuracy and case life, but that's probably about it.

i seat the bullets to the lands, but that is purely personal preference. i believe that is where i achieve highest accuracy and velocity. if you do that as well, be sure to check function in your magazine before you do a mass loading.

the bulge... not sure exactly what you are talking about. perhaps the relief in the chamber for the belt does not line up perfectly w/ the belt on your brass? after sizing my brass there is a ring in that area, but i wouldn't call it a bulge... to be on the safe side, maybe take a few once fired cases to your 'smith (a few before sizing, a few after) and have him evaluate them. or, contact rcbs and see what they think. they may want a few empties to set you up w/ a different die.

 

[wanderinwalker]

You state that the resized, yet empty cases, fit freely. Does the bolt close on these? If so, read on for a thought. If not, this won't help you much.

You state that the loaded rounds are within spec, barely. I suspect that your bullet ogives might be running hard into the rifling ahead of the chamber. My .260 will do this with 140gr Sierra Gamekings loaded to the spec of 2.80". Solution, seat the bullet deeper.

Oh yeah, the trick for establishing seating depth is to take a fired case, a bullet and a magic marker.

First, make sure that the bullet will press fit snugly into the case-mouth. Get creative if it won't, but don't resize.
Second, coat the bullet on a side with the magic marker.
Third, set bullet into case.
Fourth, chamber this setup into your rifle.
Fifth, extract round. Caution: Bullet may become lodged in rifling. A gentle tap with a cleaning rod will pop it loose.
Sixth, measure extracted cartridge (or slide bullet into case to align with the mark made).

Congrats, you now know your maximum OAL for that bullet. I believe the suggestion is to reduce this .1" and adjust from there for accuracy, but I know that's not entirely correct. Help on this please?

 

[Poodleshooter]

TMB,
I had this same problem with my A-bolt in 7mmRM while reloading nickel plated cases. Additional screwing down of the die to back the shoulder in does nothing except scrape the plating off of the bulge just above the belt. Cases are still impossible to chamber The problem lies in that expansion just above the belt, as you surmised. Dies don't actually size this tiny ring above the belt, so you would have to go with one of the newer custom dies for belted cartridges (I can't remember who is selling them, but I've seen them at Cabela's among other vendors).
I had to cull about 25% of a lot of nickle cases due to this issue. I've been trying a few things with some success:
1. Keep my loads a bit lighter to minimize stretch and "the bulge"
2. Try minimal full sizing (just bumping back the shoulder enough to chamber). I don't know why this affects the belt bulge, but it seems to for some reason.
3. Try different brass. I had some trouble with Remington nickel cases (I'm phasing out ALL of my nickel rifle cases), and also with Federal brass cases.

Let me know your results.
regards,
Pshooter

 

[The Mighty Beagle]

Thanks Poodle and everyone else who was so kind to chime in here ... I'm waiting on some new NON-NICKEL brass to arrive before I do anything else, as I foolishly full-length sized all my nickel brass before realizing what I'd done.

That silly bulge is just downright unnatural, isn't it? It's like there's something wrong with my chamber. I'm going to re-adjust my dies and pay attention to the trim-to length next time around.

It may be a little while but when I get the brass and a chance to play with it again I'll post here. Jeesh, glad I started this project this summer and not right before deer season.

 

[Bob C]

Another thing to check is the neck thickness relative to your chamber.

If a bullet won't slide into a fired, but unsized case, there may be too much metal in the neck.

This can be corrected by outside turning the case, or by inside reaming the neck.

New brass in my 7mm Rem. Mag. required both trimming and reaming after the first firing.

 

[The Mighty Beagle]

Thanks Bob, I never even thought of that. I have my 7mm stuff put up right now due to a .45 ACP loading project, but when I can I'll check that out.

 

[GooseGestapo]

Just some thoughts after reading your posts:
1.) Are you crimping your bullets ?
If you are, you may be excessively crimping causing the neck to buckle outward at crimp, or even buckle-expand the shoulder/body area. I usually see this on .30/30's by newbies that don't understand crimping.

2.) Are you trimming the brass to "trim-too" length. An over length case (many of the OFB brass I've loaded for friends 7mm Mags, have been somewhat overlength after the first firing) can cause hard chambering. I always trim any brass that hasn't been previously loaded, or at least check for length before proceeding afer sizing/decapping, as the cases "GROW", after sizing and decapping. An overlength case w/o bullet will chamber easily, but not at all after bullet is seated (at least with modest effort).



BTW, if the "buldge" you are refering to is the difference in the body diameter vs. the head section immediately in front of the belt, this is normal for most belted cases. Its the difference between the nominal case diameter and the nominal chamber dimisions. Most manufacturers use chamber reamers that when new, tend to be oversize so they can be resharpened and get longer tool life between replacements. This is one of the reasons they (belted mags) are not popular with some. Don't worry about it if after the above is checked and ruled out as cause of hard chambering.

 

[The Mighty Beagle]

Goose, I'm not using a crimp at all ... from what you say though it sounds like my brass may be too long. I never even attempted to trim it, since I deal with handgun cartridges more and don't ever trim them. I have in the past had 30-30's and other rifles that didn't require trimmed cases after the first firing though, so I didn't think this would be necessary. Guess I was wrong about that.

 

[John Galt]

It sounds like your problem has something to do with the neck / crimp / bullet / or OAL. In other words, nothing to do with the FL die.
- Trim a piece of brass short just for the heck of it with anything, dremel, whatever. Just to eliminate that issue. Probably not the problem.
- Seat a bullet way too deep and try that, to eliminate OAL. Remember, OAL is to the ogive on the bullet and all bullets are shaped different. For each different bullet you use, follow the instructions above about using the lands and a marker to determine seating depth for each bullet shape. Mark the seating die position that sets it just short of the lands.

Slightly off topic..
- For each gun I get, I follow the instructions on VarmintAl.com in re measuring my chambers. You can establish your own trim length as yours could be less, but likely more than SAMMI. I determine my max brass length, the actual distance to lands, etc.
- After firing, I try chambering a factory round. Then, I chamber an empty fired brass like you did. If it chambers fine, I try several and try to find one that has a little trouble closing the bolt. Then, I put that one in my press and turn down the FL die until it just touches the brass. Then I keep chambering the brass and turning down the FL die until that piece of brass is barely easy to close the bolt on. I mark that setting on the die and shell plate and always use that setting. On most of the brass, it will only be neck sizing.
* After all, the point is to load for YOUR rifle, not some loose SAMMI spec.

 

[redneck2]

John beat me to it...

I'd STRONGLY suggest a stop at Varmint Al's website http://www.cctrap.com/~varmint/ahunt.htm (hope this is right...that's what comes up)

Nickle cases are a no-no. He explains why.

Since this is used, I'd do a REAL good job of cleaning the chamber. I had similar problems with a .223. Soaked the chamber with a patch of solvent, then used a bore brush big enough for the chamber (not the bore) on a slow speed drill, about 30 seconds. Cleaned out the hard crud and let the rounds chamber.

Next thing I'd suspect is case length. Trim to minimum length after every firing of a mag caliber. And, check the seating depth as above.

As for neck sizing.....maybe not a good idea to back out the die for "neck only" It MAY let the base of the cartridge "float" in the shell holder and make the neck crooked giving run-out. Neck size only dies still hold the bottom of the case so the neck is straight. HTH

 

[ClarkEMyers]

Use a Wilson case gauge

Notice that resizing changes the case, that's why RCBS makes money selling X-dies.

My own practice for first cut at OAL is to seat a loose bullet against the lands and mark a cleaning rod pushed into the barrel until it stops - requires a cleaning rod into the muzzle and so some prefer to avoid that, you can even buy special tools for this job - then remove the bullet and push the cleaning rod into the bolt face - distance between marks is a first cut at OAL with that bullet.

Mostly I always use a Wilson case gauge, and double always with belted cartridges.

 

[magnum7mm]

TMB,
I had this same problem with my A-bolt in 7mmRM while reloading nickel plated cases. Additional screwing down of the die to back the shoulder in does nothing except scrape the plating off of the bulge just above the belt. Cases are still impossible to chamber The problem lies in that expansion just above the belt, as you surmised. Dies don't actually size this tiny ring above the belt, so you would have to go with one of the newer custom dies for belted cartridges (I can't remember who is selling them, but I've seen them at Cabela's among other vendors).
I had to cull about 25% of a lot of nickle cases due to this issue. I've been trying a few things with some success:
1. Keep my loads a bit lighter to minimize stretch and "the bulge"
2. Try minimal full sizing (just bumping back the shoulder enough to chamber). I don't know why this affects the belt bulge, but it seems to for some reason.
3. Try different brass. I had some trouble with Remington nickel cases (I'm phasing out ALL of my nickel rifle cases), and also with Federal brass cases.

Let me know your results.
regards,
Pshooter

I cant say for sure but I was having with my 7 mm mag and I think I have found the solution. After reloading a few times, the casing just below the belt, cant be brought back to original size with ordinary sizing dies. Larry Willis produced a collet sizing die that works slightly different from a conventional full length resizing die. I have used the die and it has brought and end to the dreaded magnum bulge. If you go to larrywillis.com you will be able to check out the die. (innovative technologies)

 

[hc1]

Just in case, check for a small lip right after you trim and debur. May have to drag your finger nail over it to feel it.

 

[627PCFan]

+100 on the Wilson case gauge. IMO its as vital as a press itself, and ditch the designer brass.

 

[snuffy]

Wow, a 5 year old thread!

There's nothing wrong with nickel cases, his trouble was NOT caused by the fact that the cases were nickel plated.

 

[magnum7mm]

Okay, this is bizarre ...

Being more of a handgunner, I have reloaded my own ammo for years, but am just getting started with rifle reloading for a recently acquired (used) Remington 700 ADL.

I cleaned and adjusted my Hornady 7mm dies and, using my Lock-n-Load progressive press, I cobbled together 5 rounds using 7828 powder and 160 gr. bullets. All the measurements via calipers were within Sierra manual specs., though sometimes just barely.

Here's the thing: re-sized, empty casings will fit in the chamber of the gun nicely, even loosely. Loaded rounds, which are in spec, fit in snugly, and allow the bolt to seemingly go fully forward ...

However, the bolt handle will not turn down without significant force applied to it. With some annoyance, I was able to shoot the rounds, which were not at all hot loads. I was afraid of tearing up my gun, so I stopped there. BTW, gun works flawlessly w/ factory ammo.

So what's my problem? I've got the stupid sizing die screwed down as far as possible. I've tried experimenting with o.a.l. of the cartridges to no avail. It's like my gun doesn't like the once-fired nickel Winchester casings, or it's like that 'belt' is getting out of spec. after one firing.

What do I do? There's no way in hell I can afford factory ammo only in this gun ....

I am new to this forum,so I hope you can read this. I have used a 7mm mag for 25/26 years. Had the same problem,it is because most conventioal dies cant squeeze the casing down enough because of the belt on the cartridge. Innovative technologies(Larry Willis.com) designed a collet die that will end your problems. Try it, I did you wont regret spending aroud 85.00.

 

[nastynatesfish]

finally a biggun

I also have a 7mm and love it. mine is a savage 110 factory gun with accu trigger. first if your bolt won't close with a reloaded round and will with a factory its because your case is to long and need to trim. all I have ever done is neck size and I think its the way to go being that your not fire forming every shot and case stretch is minimal unless your loading real hot. I load with reloader 19 and 154gr sst and load 65 gr for about 3100fps and group about 1inch. aol is 3.400 in the lands bit that's my rifle. I also started using barnes tipped tsx 120gr with 68.5gr and they are as close to same hole as you can get witgout actually being aol is 3.368. the gun shoots better with the copper bullets so I'm stickin with em. hope this helps any.