[Colorado4Wheel]

So this topic comes up fairly regularly. I thought I would post a little process on how to trouble shoot the common problem of “Why doesn’t my ammo fit my gun”. There are lots of reasons why your ammo may not be fitting your specific barrel. Remember every gun’s barrel is different. Don’t expect what works in one barrel to work in another barrel. Let’s see if we can figure this stuff out.

1) Using a case gauge vs a barrel. A case gauge is a tool that is meant to mimic a pistols chamber. Most do not make any attempt to mimic a barrels “throat”. The throat is the part of the barrel that the bullet projects into. No case gauge is going to be the same as your barrel but your barrel is also not going to check the entire round because the ramp is usually cut away a little and the rim of the case does not go into most barrels around the entire perimeter. So both have their pros and cons. The best option is barrel because it will test the throat area and that is where a lot of people have issues.

2) Let’s talk about “Sizing Issue”. Many people who load for Glocks say we have a “Glock Bulge issue”. That may be true but believe it or not a good sizing die will take out the Glock Bulge. Not all dies are created equally. Some have a pretty large taper going into the die that moves the carbide ring farther from the base and as a result the ring doesn’t size as low. Dillon and RCBS are known for this. Lee is known for sizing lower. Hornady is pretty good in this regard as well. Redding makes both kinds of dies, single stage version (no taper) and progressive version (tapered). I have not used the Redding. So how do we trouble shoot a Sizing Issue. Pretty easily. Size a bunch of cases and drop them in your barrel. No bullets. Just sized cases. Feel the way they hit the end of the chamber. Listen to the sound. Notice the depth it goes in the chamber. That’s how your loaded round should look, feel and sound when you drop it in the chamber. Sizing issues are diagnosed before you load any powder or seat the bullet. Simple isn’t it? If it doesn’t drop in cleanly you need to lower the sizing die. It can just touch the shellplate and still not bind. You need to be sure to not let the setup bind on a progressive press. If lowering the die doesn’t help you may need a better sizing die. The manufacture may give you a “Small base die” that might solve the issue. Or you can try a Lee/Hornady/Redding. You shouldn’t need to go to a push through die for the vast majority of barrels. Some manufactures of aftermarket barrels have a history of making some tight chambers. They will often work with you to open it up if you ask.

3) So the next area that gives people trouble is bullet seating issues. You run into problems in several areas. One is when you seat the bullet it can go in a little sideways causing a bulge on one side of the case that is not on the other side of the case. Usually, you can visually see the issue. Then the loaded round is too big on that side and it won’t properly chamber. This is going to normally solved with a little more flare. Flare the case .015” over the size of a sized but unflared case is normally going to be fine. You don’t need to measure it after you have become accustomed to what works and what doesn’t. If this doesn’t solve the issue you may need a custom seating stem that better match’s your bullet style.

 

[Colorado4Wheel]

4) Another thing that confuses people is what is commonly called “The Coke Bottle Shape”. It’s totally normal in most cases. As long as the round chambers without issue it’s actually preferred. This is a optical illusion created by the sizing die sizing the case smaller and then when you seat the bullet pushes the case out to the size of the bullet. Basically, it "looks" like the case is bulging at the base of the bullet after you insert the bullet. After the bullet ends the case returns to it's normal smaller size again. Hence the “Coke Bottle” name. The deeper you seat the bullet the more likely it is to look like this. Also, the smaller the case is sized the more it will “look” like it’s bulged. It’s actually a good thing to have a case that is a little smaller then the bullet diameter. This is what creates bullet tension and prevents bullet setback. Because cases are thinner at the top and thicker at the base, the deeper you seat the bullet the, the wider the case becomes when you insert the bullet. If the bulge is too large that it causes issues with chamber you’re going to need to load longer.

5) The other issue created when you seat a bullet is a OAL (overall length) issue. Basically the loaded round is too long and the bullet hits the throat. The only way to resolve this issue thru trial and error. The way I do it is to load the round long, remove the flare (don’t crimp inward). Drop the loaded round in the chamber. Then shorten it up till the round drops in freely with a nice “thunk”. Load it at least .005” shorter then that length just to be safe. You may want to go even shorter. If you make a dummy round at the right length you can use this round in the future to reset your seating die to the same length. Just put the round in the shell holder. Lower the handle. Screw the dies adjuster down by hand till it contacts the bullet of your dummy round. Set the die and your done. Simple.

6) Flare is another area that causes issues. Don’t over flare. Never more the .020” over unflared size. Don’t under flare either. It can cause the bullet to not seat straight. .010 is about the least I like. But you can experiment and find what works for you.

7) Crimp is very misunderstood. In an autoloading pistol (9mm, .40, 45acp, etc) you only remove the flare. You do not crimp inward. Yes that seems odd. But it’s true. Crimp does not hold the bullet in place on a autoloader. Bullet tension through sizing holds the bullet in place. If you look at the picture in the Lyman manual you will see that the taper crimp picture does not show the crimp going inward and denting the bullet. Revolvers do have a actual crimp. They get the edge of the case rolled inward. This is called a “roll crimp”. Your reloading manual has a good picture of this. Over crimping a pistol round can cause a bulge lower in the case. It can also cause accuracy and other issues. Many people don’t deflare enough. So the loaded round does not go into the chamber. It’s hard to tell if it’s a OAL issue or a Crimp issue at this point. First thing I do is use my dial calipers. You can use the skinny end of your calipers to measure the remaining flare at the end of the case. You will see the needle or the number grow larger as you measure the very end of the case vs the part just before the flare. You can also use the calipers as a double straight edge. Place the loaded round between the jaws of the calipers and hold the setup to a bright light. You will see the bumps and flares of the case very clearly like this. Remove flare till the case goes in properly.

8) Keep in mind on a progressive press your Flare, crimp, OAL and sizing will change if your loading with a Full Shellplate vs one station at a time. Always make adjustments with a Full Shellplate. You can use dummy rounds and empty cases to duplicate this effect.

9) Where people often go wrong in trouble shooting these things is they just randomly start to change things. They don’t have a system to figure it out. Basically, when you set up your dies the first time you should check the sizing die out. Make sure it’s sizing the case properly to drop into the barrel cleanly. Problem solving a sizing issue after you seated the is very difficult. Check your sizer with just the empty case. After that you check OAL and Crimp. If you run into issues with a caliber I will first look at the crimp. Sometimes brass is different and the flare is not getting removed properly. It’s easy to visually see this or measure it as I said above. If crimp is right then the next thing to check is OAL. Try seating the bullet .010” shorter. Did that help? If not then go shorter. Lead is often seated very short compared to FMJ. Check your manual for Lead OAL, that might help. If you’re seating shorter than the OAL of your load data you need to work the load up again to be sure it’s safe. If you’re thinking the OAL is not the issue go back and look at the sizer setup (recheck a sized case in the barrel). If the case goes in properly then take the loaded round and roll it on a flat surface. Watch the bullet tip. Does it wobble? If so then you have a bullet seated crooked. Check every step individually and you will find the issue.

Hope this helps.

Let me know if I missed something.

 

[squirreld]

good write up!

 

[Zombie Steve]

You forgot part 9... placing your Lee FCD in the trash can.

:whistling:

 

[Beanie-Bean]

C4W,

Thank you for taking the time to post this. I can tell you that you've helped at least one person (again!) and have scared me off ever considering an FCD for anything.

Particularly interesting idea was the case gauge/barrel testing--I check the dummy rounds from the magazine after they pass the gauge check. If they chamber and eject properly, I'm pretty much done at that point and will continue loading at those settings. However, I was intrigued by the empty shell and drop tests you mentioned, and will try that during tomorrow's session.

 

[EL_NinO619]

A+ Brother... And I just thought you where a evil person and would never help anyone :supergrin:.. Or this may just be away for you to avoid ignorant question.:dunno:

 

[FLSlim]

Good job, time for another sticky....

 

[thorn137]

The other issue created when you seat a bullet is a OAL (overall length) issue. Basically the loaded round is too long and the bullet hits the throat. The only way to resolve this issue thru trial and error. The way I do it is to load the round long, remove the flare (don’t crimp inward). Drop the loaded round in the chamber. Then shorten it up till the round drops in freely with a nice “thunk”. Load it at least .005” shorter then that length just to be safe. You may want to go even shorter.

I've always messed around with smoking bullets, or sharpie pens, with barely acceptable results at times... this tip is excellent. So simple that I feel stupid for not thinking of it - so - Thanks for posting it.

thorn

 

[Shadyscott69]

:rock:

 

[rpgman]

thanks for taking the time to write this up.
Greg

 

[ChrisJn]

Very well written and easily understood. Good job, Steve.

 

[Hogpauls]

Thanks C4W, great write up! I've been having some accuracy issues and I'm sure my crimp is the problem and you just verified it.

 

[jmorris]

Usefull info for subjects that are posted often.


The case gauge is the #1 cure for those mystery malfunctions as the barrel drop doesn't check not only the ramp but also the part that is in contact with the breech face. Dings caused by prior firings and contact with ejector/extractor is what you catch with the case gauge. Those same dings are also fixed by push through and roll sizers.

 

[TexasFats]

One added note on crimp: The reason why we don't want to force the case brass into the bullet with too much crimp when loading for an autoloader like a 1911, etc., is that these guns are designed to headspace on the case mouth. If you look down the barrel of an autoloader from the chamber end, you will see a slight shoulder at the end of the chamber. The case mouth butts against this shoulder for headspacing. That is why revolvers firing the .45 ACP need half-moon or moon clips, or have to use the .45 Auto-Rim. Their chambers don't have this shoulder for the case mouth, unless specially chambered.

 

[jmorris]

That is why revolvers firing the .45 ACP need half-moon or moon clips,

The two I have fire just fine without moon clips. The reason you need moon clips is to eject the brass. They would also be needed if the revolver was chambered for 45 long colt not ACP.

 

[GioaJack]

I shoot my Smith model 25 all the time without clips, easier than loading and unloading them. For those cases that don't fall out when the gun is inverted it's a simple matter to push them out with a pen or anything else that is handy.

Headspacing on the case mouth is one of the most misunderstood myths when it comes to the necessity of being precise with taper crimping.

Over the years, many years, I've done countless tests on over crimping both 9's and .45's to the point where they resembled very aggressive roll crimps that could not possibly headspace on the case mouth. (Accuracy was not a concern just an attempt to get the rounds to malfunction.

In guns ranging from Smith models 39 and 59, BHP, Colt Gold Cups, various Colt 1911's, Star PD and countless others I have never had a single occasion where the extractor didn't hold the round in place and allow the round to fire normally.

This is not to suggest that a taper crimped round should be needlessly be crimped more that necessary but simply to demonstrate that the crimp is not as critical as some would believe.


Jack

 

[Duck of Death]

*QUOTE*
and have scared me off ever considering an FCD for anything.

Why????

 

[TexasFats]

The two I have fire just fine without moon clips. The reason you need moon clips is to eject the brass. They would also be needed if the revolver was chambered for 45 long colt not ACP.

You are right. I had forgotten that. That is also why the .45 Auto Rim was invented, so that the ejector star would have something to use to push the cases out of the cylinder.

 

[TexasFats]

I shoot my Smith model 25 all the time without clips, easier than loading and unloading them. For those cases that don't fall out when the gun is inverted it's a simple matter to push them out with a pen or anything else that is handy.

Headspacing on the case mouth is one of the most misunderstood myths when it comes to the necessity of being precise with taper crimping.

Over the years, many years, I've done countless tests on over crimping both 9's and .45's to the point where they resembled very aggressive roll crimps that could not possibly headspace on the case mouth. (Accuracy was not a concern just an attempt to get the rounds to malfunction.

In guns ranging from Smith models 39 and 59, BHP, Colt Gold Cups, various Colt 1911's, Star PD and countless others I have never had a single occasion where the extractor didn't hold the round in place and allow the round to fire normally.

This is not to suggest that a taper crimped round should be needlessly be crimped more that necessary but simply to demonstrate that the crimp is not as critical as some would believe.


Jack

Jack, if .45 ACP, .40 S&W, 9 mm, etc. don't headspace on the case mouth, then what do they headspace on? They don't have either a rim or a shoulder for headspacing. Also, if they don't headspace on the mouth, then why do some pretty reliable sources (Hornady, Speer, Sierra, Lyman, et. al.) say that they do in their manuals. Also, I have some snap caps in each of those calibers, and, I guarantee, those snap caps all show that each blow of the firing pin drives the cap up against the shoulder in the chamber where the case mouth would contact if it were a live round.

Of course, the ejector hook could be holding the cartridge enough to allow a firing pin blow to fire the round. But, that does not mean that the results from your experiments indicate that it is safe to fire such rounds. To determint that, one would need a pressure gun to measure the chamber pressure on your rounds. Personally, I'll just follow the manuals that have done some testing with proper pressure equipment and not crimp, or just put a very mild taper crimp on stuff like .45 ACP.

 

[PCJim]

Jack, if .45 ACP, .40 S&W, 9 mm, etc. don't headspace on the case mouth, then what do they headspace on? They don't have either a rim or a shoulder for headspacing. Also, if they don't headspace on the mouth, then why do some pretty reliable sources (Hornady, Speer, Sierra, Lyman, et. al.) say that they do in their manuals. Also, I have some snap caps in each of those calibers, and, I guarantee, those snap caps all show that each blow of the firing pin drives the cap up against the shoulder in the chamber where the case mouth would contact if it were a live round.

Of course, the ejector hook could be holding the cartridge enough to allow a firing pin blow to fire the round. But, that does not mean that the results from your experiments indicate that it is safe to fire such rounds. To determint that, one would need a pressure gun to measure the chamber pressure on your rounds. Personally, I'll just follow the manuals that have done some testing with proper pressure equipment and not crimp, or just put a very mild taper crimp on stuff like .45 ACP.

Me thinks you misread Jack's post. He was DELIBERATELY attempting to prove that, while those cartridges are designed to headspace on the case mouth, they will usually fire when being held by the extractor.