Key word is "maximum" . . .

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Prof Young

New member
So I've been loading 45 ACP for a year or so now without any problems. Today at the range I was having all kind of trouble getting them into the magazine. Kept binding up. Thought it was the mags at first but then put some factory loads in and they ran just fine. Must be my ammo. I was mystified as I'd carefully sized all the cases. Got home and popped some of the reloads in my case gauge. Everything it fine. I try to stuff some in the magazine again and noticed that the bullets were touching the front wall of the magazine. They were too long. My Lee die instructions says the maximum length is 1.275 inches. These latest loads were 1.270. Previously I'd been around 1.26 and 1.25. I think I assumed so long as I was below the "maximum" I'd be okay. Wrong.

I reseated them all a touch deeper and all is well.

So much to learn about all this loading and shooting stuff.

Life is good.
Prof Young
 
Your COL (Cartridge Overall Length) is determined by your barrel (chamber and throat dimensions) and your gun (feed ramp) and your magazine (COL that fits magazine and when the magazine lips release the round for feeding) and the PARTICULAR bullet you are using. What worked in a pressure barrel or the lab's gun or in my gun has very little to do with what will work best in your gun.
Take the barrel out of the gun. Create two inert dummy rounds (no powder or primer) at max COL and remove enough case mouth flare for rounds to chamber (you can achieve this by using a sized case—expand-and-flare it, and remove the flare just until the case "plunks" in the barrel).
Drop the inert rounds in and decrease the COL until they chamber completely. This will be your "max" effective COL. I prefer to have the case head flush with the barrel hood (or a few mils higher than where the head of an empty case aligns with the barrel, as all cases are too short and I prefer to minimize head space). After this, place the inert rounds in the magazine and be sure they fit the magazine and feed and chamber.
You can also do this for any chambering problems you have. Remove the barrel and drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop this round in the barrel and rotate it back-and-forth.
Remove and inspect the round:
1) Scratches on bullet--COL is too long
2) Scratches on edge of the case mouth--insufficient crimp
3) Scratches just below the case mouth--too much crimp, you're crushing the case
4) Scratches on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit
5) Scratches on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.
 
1.275" is SAAMI Max for any .45 ACP bullet. Your loads not fitting means the pistol's mag is a tick short. You reseating them all a touch deeper is the easiest and least expensive fix.
 
Prof Young,

It depends on the nose shape of your bullet. The front edge of the magazine is intended for RN military ball. For a wider shape to work, it may have to be seated to fit within the profile of the RN FMJ. I made you a picture, leaving the case out. On the extreme right it shows how much deeper that TC profile needs to be seated to be sure the magazine will like it. That still doesn't prove your feed ramp will like it, though. That's a separate issue for a reliability package from the gunsmith.

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Great illustration Unclenick.

Note, the TC bullet's corners would be outside the RN boundary even more if it was seated to the same OAL - as opposed to the same seating depth.
 
Thanks for all the good info.

Thanks for all the good info and suggestions.

Learning, learning, learning . . .

Life is good.
Prof Young
 
For what it is worth ... I was loading 230 gr LRN at 1.265 OAL. The bullets had a slight shoulder protruding about 040 or so in front of the case mouth, which occasionally resulted in shaved lead during seating/crimping, and not all passing the plunk test. My last batch I loaded to OAL of 1.225. They all passed the plunk test and fed just fine. I kept the same 5.5 gr Unique, and got only 10 fps greater speed. So at least with 45 ACP shorter is fine.
 
Up to a point, that's so. From the 0.040" shoulder number, I am guessing you have one of the cast bullet shapes with a shorter, more hemispherical nose than the elliptical military FMJ nose. The military ball bullet is a whopping 0.680" long.
 
No worries OP, I have had this same exact thing happen to me.

My SIG p227 will choke on many round nose bullets if loaded longer than 1.25" COAL while my M&P45 will feed and fire them just fine even beyond 1.275".

You may have this "problem" again if you switch to a different brand of bullets, just load a few to start and make sure they feed well.

I make a few dummy rounds without powder or primer and try cycling them in my various 45's before loading in quantity.
 
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