[bangbig]

9mm, resize/deprime, case plunks in guage and barrel. Prime said case, still plunks in guage and barrel. Expand mouth (more than needed), run through seating/crimp die (with no bullet) and case plunks in guage and barrel.

As soon as add a bullet to this process ('cept I back off on the flare to just enough to start the bullet), it must be forced into the guage and barrel.

These are Missouri Bullet 125 "small ball". They do measure slightly over @ .357" on bot a set of calipers and mics. Is this my issue? I have no other bullets to load to test with.

I am seating these to an oal of 1.110 and have seated a couple dummy rounds down to 1" and up to 1.130 and get the same results.

Thoughts?

[Lost Sheep]

Measure the outside diameter of the case in a couple of spots
A) the mouth,
B) partway down the bullet,
C) where the bullet's base is and
D) just below where the bullet's base is.

I have a hunch B and C are significantly greater than A or D and just a bit more than the inside of your chamber.

What is the diameter of a freshly fired and ejected, unsized case at each of the four points?

Comparing those dimensions will tell the tale, I bet.

Lost Sheep

[Certaindeaf]

Start with maybe the de-bell process didn't quite do it and or the OAL is too long.

[tightgroup tiger]

Possibly the bullet is seating crooked in the case, or you don't have enough flare on the case from backing the die off and are shaving the bullet into the case alone side of the bullet and oversizing the case is an end result.

If these bullets are a little oversized it wouldn't take as much on being seated a little crooked to cause problems. I don't know if .001 would do that to you but that would depend on how tight your chamber is.

Shaving bullets and having the shavings get caught in the lube groove could cause some oversize issues also I would think you should be able to measure that to see or even see it in a bulge in the case.

Just some thoughts.

[bds]

What pistol/barrel are you using? I use .377" taper crimp with them and they chamber well even in tighter Lone Wolf and KKM aftermarket barrels.

Missouri 125 gr RN (SmallBall) should be sized at .356" unless you ordered them sized larger. They usually ship generously lubed and sometimes give you larger than 356" reading on the calipers. Wipe off the surface lube and they should read more around. 356".

If they read .357" even after you wipe off the lube, double check the accuracy of calipers/mic by measuring any jacketed bullet. Perhaps you could take them down to the gun store and measure some jacketed bullets? (they should be. 355" for 9mm, .400" for 40S&W and. 451" for 45 ACP).

If the calipers check out and the bullets are indeed .357", give Brad/JoAnn a call/email and they should help you get the correct sized bullets.

[NeuseRvrRat]

what headstamp is your brass?

[918v]

Who cares if they don't pass the case gauge. I use .359" bullets in my KKM barrel and they chamber just fine. Use your chamber as a gauge and use the largest diameter bullet that will chamber in your barrel, else you'll get leading.

[ranger335v]

"It has to be oversized lead, right? "

I'm not sure what you mean but if you mean do cast bullets have to be larger than normal, the answer is NO; what would be the point of that?

[bds]

Who cares if they don't pass the case gauge ... Use your chamber as a gauge and use the largest diameter bullet that will chamber in your barrel
918v, that's what I was going to post but OP stated both gauge AND barrel were tested.

case plunks in guage and barrel ... As soon as add a bullet to this process, it must be forced into the guage and barrel.

If the OP has a tight chambered barrel, larger sized lead bullet could prevent the finished round from fully chambering by bulging the case. If the finished round is only slightly snug with the chamber, it will be OK if the slide fully returns to battery and extracts/cycled reliably. BUT that snugness should be double checked to make sure it is not the bullet's bearing surface pressing against the "freebore" or leade or both. ;)

OP, try a dummy round with 1.080"-1.100" OAL and set the taper crimp to .377" and see if that will feed/chamber reliably from the magazine.

[popper]

What gun? I think XD has a tapered chamber. I had to really seat deep to get them to work, but glock was no problem.

[moxie]

Interestingly, I just got a lot of 9mm bullets from Midway. Winchester 124 gr. FMJ. Supposed to be sized at .355". I make them at .352". Calipers are known good.

[ljnowell]

Interestingly, I just got a lot of 9mm bullets from Midway. Winchester 124 gr. FMJ. Supposed to be sized at .355". I make them at .352". Calipers are known good.


Not surprising. I quit buying winchester bullets. I have gotten 45 acp hollowpoints that are .4505 or .450. I also got some 158gr hollowpoints from grafs awhile back, I think they were sold as magtech, and they were .3555". A friend said, thats cause they are for 9mm. Unfortuantely though, they are a 158gr JHP with a blunt front and a cannalure. No way these were made for a 9mm autoloader. I ended up sending them back.

[918v]

Looks like Winchester got some brand spankin' new 9mm bullet dies.

[moxie]

A bit unsettling.

However, I'll load 'em up and I bet they go bang and hit the target. Seems to be the case most of the time. The reloading hobby is not quite as precise, all the time, as we might wish it to be.

[bds]

Hello???

OP is having chambering issues with Missouri lead bullet ... discussion about under-sized Winchester bullets won't help the OP ... :uhoh:

[moxie]

bds,

You're right. If the OP's bullets are in fact over .357" then that is likely the problem, but he hasn't chimed in in response to questions.

For the OP, bangbig. The fact that your plunk test failed does indicate the bullets are too big, when combined with your raw bullet measurements. BTW, plunk testing components before you have a complete round doesn't get you much. I'd call MBC as others have suggested.

[bangbig]

Wow. Lots of input. THANKS!!!

Ok, lots to check here. Firearm is Kahr CM9. Case gauge is Lyman max pistol gauge. 3 different factory loads plunk in and out of both the gun and the gauge. Expanding and de-belling an empty case still passes both.

I've tried three different brands of brass. All are well under max length.

Don't have the numbers handy, but the case diameter is in at the mouth with bullet loaded. I'm thinking the seated bullet expands the case just enough that there is still a taper to the larger diameter (which is in spec), but at a faster rate so there is a point somewhere along where the bullet is seated that is too large if that makes any sense?

IOW the diameter is ok but the taper is not.

I'll def contact MBC and see what they say.

[OEH]

I have a batch of Missouri Small Ball that won't work in 3 of my 4 9mm's either. They measure .357 also. I'll end up using them in some .38 Spl. loads eventually. Went back to Berry's.

[bangbig]

I have a batch of Missouri Small Ball that won't work in 3 of my 4 9mm's either. They measure .357 also. I'll end up using them in some .38 Spl. loads eventually. Went back to Berry's.

That's interesting.:uhoh:

Thinking about pulling a bullet from a factory round and loading that. Or would that even tell me anything but the fact I can get good results with FMJ but not lead?:confused:

[bds]

Using pulled jacketed bullets won't help as they are sized at .355" and probably have decreased diameter after being taper crimped and run through finishing die. By contrast, Missouri lead bullet is sized at .356" and will bulge the case quite a bit.

Brad did mention in past threads/facebook page (http://www.facebook.com/missouribullet) that a past employee was a little sloppy and some boxes were sent out mis-sized. You may got lucky and bought one of those boxes. If the bullets are indeed mis-sized, call Brad/Jo Ann and they'll make it right (it's their policy ;)).

Here's a comparison between 115 gr Winchester FMJ, 125 gr MBC 125 gr RN and 125 gr SWC showing the case bulge (yes, they all plonk right into Lone Wolf and KKM barrels).

http://www.thehighroad.org/attachment.php?attachmentid=152505&stc=1&d=1320990449

Here's a little better picture as it doesn't have much "optical illusion" effect (I need to take some better pictures).
http://www.thehighroad.org/attachment.php?attachmentid=165329&stc=1&d=1338342403

[918v]

I have a batch of Missouri Small Ball that won't work in 3 of my 4 9mm's either. They measure .357 also. I'll end up using them in some .38 Spl. loads eventually. Went back to Berry's.


Which 9mm's are those?

Because almost every factory 9mm pistol on the planet will accept a .357" bullet. Most have .358" bores.

[1SOW]

Because almost every factory 9mm pistol on the planet will accept a .357" bullet. Most have .358" bores.

Mine doesn't. My son's doesn't. CZ 75B & CZ SPO1 Shadow. Also have 'short' chambers like the XD does. "Eastern European" sized.

[918v]

Freebore length does not have anything to do with the diameter of the bullet. The freebore diameter is what dictates bullet diameter.

[DaveInFloweryBranchGA]

The one thing I don't see above is you need to start with slugging your bore and measuring the groove diameter to see where your barrel is at. A good lead bullet for your pistol would be between .001" and .002" larger than the groove diameter. This would allow the bullet to seal the groove, preventing gas cutting and therefore leading.

Google slugging a barrel and follow the instructions. Should find something with lead fishing weights and wooden dowels that works for your pistol.

[Lost Sheep]

I thought the original post was asking about difficulty chambering. The bore diameter, while important, would not affect that unless the ogive of the bullet actually got so deep into the chamber that it hit the bore. I believe he ruled that out when he tried these different OALs

I am seating these to an oal of 1.110 and have seated a couple dummy rounds down to 1" and up to 1.130 and get the same results.


as reported in post #1.

I am not trying to argue the importance of bullet-to-bore fit, but only to figure out the chambering problem.

Lost Sheep

[918v]

I am not trying to argue the importance of bullet-to-bore fit, but only to figure out the chambering problem.

I'm not arguing bullet to bore fit either. I'm arguing bullet to freebore fit, which does affect OAL. If the freebore is short, the ogjive will hit the rifling sooner than if the freebore were longer. But in his frustration, the OP is considering sizing the bullet smaller, and this is absolutely the wrong thing to do.

[Walkalong]

Some posts went away. Lets stay on topic, and lose the arguing. The OP isn't helped by it.

[OEH]

When loaded to 1.150 min COL per Lee's reloading manual they don't chamber in my:
Browning HP
FN FNX
Taurus 709
but they will chamber in my S&W 909.

I tried seating to 1.120 as a non firing test round and it would chamber in the FNX but still not in the BHP and 709.

And FWIW I never said that they would not go through the bores, I said that "they wouldn't work" in my pistols. I think it may have more to do with the shape of the bullet vs. chamber than the 1 thousandth oversize. Since I don't want to make pistol specific ammo and I don't yet feel comfortable in going "off the books" to brew up new loadings, I switched back to Berry's plated bullets for my 9mm and will use the .357 sized Smallball in some other application. YMMV

[bangbig]

MBC replied to an email sent off this morning! Seem to think the bullet is the issue as well. Fired off a couple more questions/comments and we'll go from there. Seems like they are willing to make me happy regardless.

Regarding bullet to free-bore, I thought varying oal's would confirm that, no?

Also, I do not want a round that will only fit a specific firearm. If it doesn't fit ALL 9mm's/max case gauge, that is all that matters to me. I want ammo that will fire in the Kahr in question as well as the wife's Glock, or any other that may come along.

Maybe this is not possible with this particular bullet style???

[bds]

MBC replied to an email sent off this morning! ... Seems like they are willing to make me happy regardless.
Yes, great company.


Also, I do not want a round that will only fit a specific firearm. If it doesn't fit ALL 9mm's/max case gauge, that is all that matters to me. I want ammo that will fire in the Kahr in question as well as the wife's Glock, or any other that may come along.

Maybe this is not possible with this particular bullet style???
I also load for multiple pistols (family/friends/neighbors who may join me to the range) and need to ensure the finished rounds will feed/chamber in their pistols. Lone Wolf barrels have just about the tightest chambers I know (Yes, even tighter than KKM) and will allow .377" taper crimp round to fall in the chamber freely and 1.080"-1.100" OAL will feed/chamber reliably from the magazine in most pistols.

[918v]

Maybe this is not possible with this particular bullet style???

Not possible with 9mm lead bullets. With them you need a perfect fit otherwise they'll lead up the barrel. Bullet to freebore fit is not necessarily confirmed by varying the OAL, as the bullet nose may hit the top of the lands before the shank ever makes it into the freebore.

I use Missouri's Cowboy #2 at 1.040" OAL in my 9, and it is snug in the freebore and touching the rifling. I think maybe that is what you need. Lee 357-125-RF .358" bullets have been successfully used in the CZ in that OAL range. And they are alot more unforgiving of short freebores. Good accuracy and no leading.

[918v]

http://www.missouribullet.com/cw3/assets/product_expanded/smallball.jpg

Look at how short the nose is vs the shank. These have to be loaded short.

http://www.qualitycastbullets.com/files/img_4229_0.jpg

Now this bullet is designed to be loaded long. See the long nose and the short shank?

Why dont you seat yours short and see how they shoot.

[Lost Sheep]

I am still suspecting that these bullets are bulging the cases (either at the mouth or further down the case) enough to impede chambering.

I have looked through the thread and still do not see where that has been ruled out with certainty. The O.P.'s post #17 notwithstanding. Thick casing walls, oversized bullets or an undersized chamber or a combination of those factors, I think, could be the source.

My first thought (see post #2) is to measure the diameter of a freshly fired case (which would be the closest approximation to a chamber cast as I can think of without actually doing a chamber cast) and compare to a loaded round.

Lost Sheep

p.s. If the OAL or ogive is suspected, I suggest painting the nose of the bullet, chambering/extracting the round and inspecting the paint for marks from anything impeding chambering. White-out should work.

[918v]

Bangbig:

What is the diameter of your fired cases from that CZ at the case mouth?

[bangbig]

Great idea!!!!! I painted a loaded round with a sharpie, bullet and brass. The "stopping point" is the case. Prolly about where the bottom of the bullet would be or just above. Flared brass more, same. Flared brass less to the point where I struggled to get a bullet to stay put to seat, same.

So, Id have to say these bullets are expanding the brass to the point where they will not go in a max cartridge gauge which is apparently REAL CLOSE to what the chamber is.

Ok, guess I'll see if MBC has some that are at .356. These are def .357 wiped clean of lube. Still can't believe .001 makes that much diff?!

Mystery solved?

[bds]

bangbig, for my tight chambered Sig 1911 and Lone Wolf barrels, .001" will make all the difference whether they will fully chamber or not.

Looks like you may have gotten a box of .357" sized bullets. Let us know how the .356" sized bullets work out for your pistol/barrel.

[Walkalong]

While not overly common, you could have an undersized chamber. It happens. Most 9MM chambers are generous.

[918v]

Mystery solved?

I doubt it. What do your fired cases measure. Your fired cases are a true representation of your chamber, not the case gauge.

[James2]

Hmmmm, lots of good ideas.

Sometimes a too tight crimp can bulge the case a bit. Also shaved lead can be a problem. Use enough bell to allow the bullet to seat with no shaving, and set the crimp to just take out the belling.

If these things are right, the bullet diameter and brass thickness are the other things to look at. My Lyman manual suggests cast bullets at .356.

[bangbig]

I doubt it. What do your fired cases measure. Your fired cases are a true representation of your chamber, not the case gauge.

But I want it to fit the case gauge as I want these loads to fit in ALL guns. So why would it matter what my chamber is if any load that fits the gauge fits my chamber?:confused:

[918v]

Because if you use a lead bullet sized small enough to pass your case gauge, it will severely lead your CZ.

It is not possible to create a load using a lead bullet that will pass your case gauge and fit in all 9mm's and won't lead in any of them. If you want to shoot lead, you have to make the load gun specific. Otherwise use plated .355" bullets.

[bds]

Bangbig, I load for multiple pistols and use the smallest barrel/chamber as my working "gauge". ;)

I typically use Lone Wolf barrels as my chamber "gauge" for 9mm/40S&W as they have tighter chamber than most factory barrels and Sig 1911 barrel for 45ACP.

Missouri 125 gr RN sized at .356" with. 377" taper crimp at 1.080" - 1.100" OAL have worked well in various pistols, even in Lone Wolf barrels.

[Lost Sheep]

Is this a case where the Lee FCD (Factory Crimp Die) might be of use?

The FCD has a feature (aside from providing a convenient crimp) that sizes the finished cartridge, supposedly guaranteeing the round will chamber in any SAAMI-spec chamber.

That is the sole purpose of the Post-Sizing function.

Now, I will admit that this post-sizing (especially with lead bullets) sometimes creates new problems (reducing neck tension, allowing setback while cycling through the action and reducing lead bullet diameter, which may set you up for leading of the barrel). But aside from those things (which MAY OR MAY NOT occur), it seems to me that the FCD might cure the chambering hesitation.

Lost Sheep

Edit: Yes, pay attention to bds' post #44. I am well aware of the dangers of insufficient neck tension and sending undersized bullets down the bore and did not emphasize them. I have not found them to be common, but I believe they are real.

But if the bore is the right size for these bullets AFTER them being compressed by the FCD's post-sizing, AND bullet setback does not become a problem the FCD would be a more convenient solution than re-sizing all these .357" bullets, you think? It would not be as good a solution as having bought properly sized bullets in the first place, but if it works, it works.

On the other hand, we still have not ruled out that the chamber itself could be undersized and a gunsmith's attention to the GUN would solve the RELOADING problem.

I am just brainstorming here.

[bds]

Lost Sheep, only if FCD's carbide sizer ring has been enlarged for .356" lead bullet (I think Lee Precision provides this service for $15).

Trouble is that Lee Precision meant for the carbide sizer ring to work with .355" diameter jacketed bullets.

Running the finished rounds with larger sized (.357") bullets through the FCD will certainly post-size the lead bullet diameter (how many time have you read "bullet fit to barrel is king?") and although the finished rounds may feed reliably into the chamber, you will definitely decrease the bullet-to-barrel fit (which will increase leading) and neck tension, especially with thinner and work hardened cases, that will result in bullet setback when the bullet bumps the feed ramp.

For me, best way to check neck tension and bullet set back is to measure the OAL before and after feeding/chambering from the magazine and manually releasing the slide. If you see decrease in OAL by several thousandths, you have bullet set back that may increase chamber pressure, especially if you are near max load data.

[918v]

The 9mm FCD does not touch the case neck.

[bds]

Yes, I stand corrected - almost.

For the 9mm "tapered case", FCD's carbide sizer ring won't touch the "case mouth" with both .356" and .357" sized lead bullets (had to take out my 9mm FCD to check), but the FCD's carbide sizer ring just starts to touch the "case neck" at the base of the seated bullets. ;)

Having said that, use of 9mm FCD still won't resolve OP's chambering problem as the FCD will simply reduce the lower most portion of the seated bullet and not the case mouth portion (which I think is preventing the finished rounds to fully chamber).

I still think the OP has a tight chambered barrel and received a box of .357" sized bullets and if that's the case, .356" sized bullets with .377" taper crimp should allow the finished rounds to fully chamber.

I guess we'll find out in time.

[918v]

I disagree.

From what I gather, his chamber is not tight. His freebore is short, but not tight. He is unnecessarily concerned with his case gauge. He should figure out his freebore diameter, use the right size bullet, seat short enough to chamber in all his 9s, and test the stuff.

[Lost Sheep]

Yes, I stand corrected - almost.

For the 9mm "tapered case", FCD's carbide sizer ring won't touch the "case mouth" with both .356" and .357" sized lead bullets (had to take out my 9mm FCD to check), but the FCD's carbide sizer ring just starts to touch the "case neck" at the base of the seated bullets. ;)


It will if the bullet bulges the case mouth enough to make over SAAMI specs.

That is assuming the FCD was properly made. Assuming the chamber is not too small. Assuming the ogive of the bullet is not hitting the rifling.

This could happen if the brass is thick-walled (in addition to the .357" bullets). It SHOULDN'T; the taper crimp should squish the case mouth to chamber fit, but just below the mouth, it might not be enough. I just do not have enough information to make a blanket statement.



Having said that, use of 9mm FCD still won't resolve OP's chambering problem as the FCD will simply reduce the lower most portion of the seated bullet and not the case mouth portion (which I think is preventing the finished rounds to fully chamber).

I tend to agree that it is the case mouth causing the problem, but the FCD is SUPPOSED to take care of that, isn't it?


I still think the OP has a tight chambered barrel and received a box of .357" sized bullets and if that's the case, .356" sized bullets with .377" taper crimp should allow the finished rounds to fully chamber.

I guess we'll find out in time.
That does seem most likely.

Lost Sheep

[murf]

get a factory round, your reloaded round, your calipers and start measuring. you will eventually find a difference between the two rounds.

if you don't, you have a problem with your weapon.

murf

[bds]

Lost Sheep, I think so.

At this point, all we have that is essentially factual is that the OP bought some .357" sized 9mm lead bullets.

I gave OP the consideration that the taper crimp used on the case, OAL used and the accuracy of the calipers and micrometer are good. Only thing I would have suggested for the OP to check is crushing of the case during seating and bulging the case, but that may not be the case here as OP indicated sufficient flare was used to seat the bullet.

That leaves the tightness of the chamber in question.

If the OP's problem disappears with .356" sized bullets, all of our guessing/discussions would be moot. :D

Instead of any further analysis, I am going to wait on the OP to report back. ;)

[918v]

I think the OP said the case gauge is the problem, not the barrel, there is no way in hell a pistol manufacturer would cut a chamber this tight.

[Walkalong]

I am going to wait on the OP to report back.We really do need more feedback from the OP.
there is no way in hell a pistol manufacturer would cut a chamber this tight.On purpose.

[bds]

OP said the case gauge is the problem, not the barrel
OP did post the problem was with both the case gauge and the barrel

It has to be oversized lead, right?
9mm, resize/deprime, case plunks in guage and barrel. Prime said case, still plunks in guage and barrel. Expand mouth (more than needed), run through seating/crimp die (with no bullet) and case plunks in guage and barrel.

As soon as add a bullet to this process ('cept I back off on the flare to just enough to start the bullet), it must be forced into the guage and barrel.

[918v]

Yes but he also said when he backed off the OAL the case did not need go be forced into he barrel. He was perplexed shy the OAL needed to be do short.

[bds]

In my post, I quoted that OP backed off the taper crimp, not the OAL.

Besides. OP already did a marker test rcmodel usually recommends and found that it was the case rubbing and not the bullet hitting the rifling that prevented the round from fully chambering. I really think we need to hear back from the OP before we continue with this issue.
I painted a loaded round with a sharpie, bullet and brass. The "stopping point" is the case. Prolly about where the bottom of the bullet would be or just above

[918v]

I read post #35 to mean his round is rubbing the case gauge, not his actual chamber walls.

He won't disclose the fired case diameter which would prove the diameter of his round (and the bullet diameter) is not the problem.

He wants a lead bullet handload to pass a case gauge, and not to work as it should in hid gun. You are all assuming the actual chamber in his Kahr is undersized by something like .005" which is impossible. As much as I dislike Kahrs, even they have standards.

[Lost Sheep]

I read post #35 to mean his round is rubbing the case gauge, not his actual chamber walls.

He won't disclose the fired case diameter which would prove the diameter of his round (and the bullet diameter) is not the problem.

He wants a lead bullet handload to pass a case gauge, and not to work as it should in hid gun. You are all assuming the actual chamber in his Kahr is undersized by something like .005" which is impossible. As much as I dislike Kahrs, even they have standards.
Post #2 suggested measuring a fired, unsized round.

.005" undersized chamber is possible, especially if there is fouling involved, but as you surmise, unlikely. Factory ammo does seem to feed properly, I believe. However, I have not ruled out the possibility of an undersized chamber.

I think he does not care if the bullet passes a case gauge. What would be the point in that? If it passes the barrel test (the real one, while shooting) I think the original question would have been quite different, like, "What is wrong with my case gauge?"

I have been assuming all along that the chamber is properly dimensioned, but that the case is getting bulged somehow. The question is how? The answer would be hinted at by knowing where on the case the binding is occurring. But we don't know that, yet. The OP is the only one who can help very much there, but speculation does have some value. Conclusions based on speculation do not.

Lost Sheep

[bangbig]

.356 lead on the way from MBC. We'll see what happens with that!

[bangbig]

OP did post the problem was with both the case gauge and the barrel

Yep, both gauge and barrel.

[bangbig]

Yes but he also said when he backed off the OAL the case did not need go be forced into he barrel. He was perplexed shy the OAL needed to be do short.

Not so, still needs forced regardless of oal.

[bangbig]

If chamber was undersized, wouldn't the resized cases have issues without the bullet? No issues until bullet is introduced.

[Lost Sheep]

If chamber was undersized, wouldn't the resized cases have issues without the bullet? No issues until bullet is introduced.
No, not likely. A resized case would HAVE to be no larger in diameter than an unresized case. The unsized, fired case should rechamber without difficulty. So, a resized case should be that much easier to chamber. Until it gets bulged (either by insertion of an oversized bullet, insertion of a properly sized bullet where the case walls are over-thick or some other, as yet unexplained cause).

I just wanted to see where the bullet being seated bulges the case (how far from the case mouth and by how much) larger in diameter than the fired, unsized case.

I think it might be informative.

Lost Sheep

[Walkalong]

I'd love to see some good pics with some measurements.

[Iron Sight]

Lee lead bullet size kit.

While back I bought a bunch of 45 that were not correctly sized. Using one of lees kis solved the problem.


http://www.midwayusa.com/product/343992/lee-bullet-lube-and-size-kit-356-diameter

[bangbig]

Got some .356" from MBC today. Loaded 3 rounds without changing anything in my set up. Plunk right in the barrel and slide EASILY into the case gauge.

Fired the 3 rounds off hand at 10 yards with a light (maybe not so light as these are were still seated at 1.110) load of 231 and got a very nice group.

The case from that round AFTER being fired measured .384, .388. and .390 from mouth to bottom. Where does that fall in the "chamber size" range???

[bds]

Looks like you may have gotten a box of .357" sized bullets. Let us know how the .356" sized bullets work out for your pistol/barrel.
Got some .356" from MBC today. Loaded 3 rounds without changing anything in my set up. Plunk right in the barrel and slide EASILY into the case gauge.
Great! Looks like it was the case of oversized bullets. Now, I would focus on identifying the powder charges that produce accurate shot groups while minimizing leading in your barrel.

I love happy endings. :D

[918v]

The case from that round AFTER being fired measured .384, .388. and .390 from mouth to bottom. Where does that fall in the "chamber size" range???

If your fired cases measure .384" at the case mouth, then there is no way in hell a .001" difference in bullet diameter would have caused an interference issue in the chamber. Your loaded round measured what, .378" ? That's z clearance of .006". Going to a .356" bullet gave you an additional .001" for a total of .007"?

Going to a smaller bullet allows you to increase OAL. That's basic geometry. But now you'll have to deal with leading.

[bds]

For me, I found fired case mouth dimensions to be variable depending on the condition of the brass and how much spring-back there is.

[918v]

I have found brass springback to be no more than .001" no matter what the condition of the brass, even after 35 reloads in a single sitting.