I just picked up a used Springfield Armory .45 ACP. My reloads are failing to fully chamber and I suspect a very tight chamber. My reloads function perfectly through my Sig.

Sierra 185g JHP
12.5g of AA#7
Win cases
Win LP primers

Sized cases come out .471” (O.D.) out of my Lyman dies. Bullets check at .451”. When seated the cartridge mouth measures .472”, case length in spec. When I hit the slide release the cartridge only feeds in half way and the slide cannot be pushed closed.

OK, so I dig out the taper crimp die figuring it may help, yup it puts on a nice taper and the cartridge mouth now measures .469” but now the bullets fall out. They chamber well but the bullet will not stay in place. Any ideas short of sending it to a gunsmith to polish out the chamber?

1. Remove the barrel from the pistol. Use it as a "chamber checker" (assuming you don't have one).

2. Start with a factory cartridge if you have one and see if it falls all the way into the chamber and headspaces on the case mouth as it should.

3. Then try the reloads... in stages. Size a case and see if that will headspace correctly without the bullet seated (no belling). If not, then the chances are that the case is not being sized low enough towards the extractor groove. It is common when you shoot picked up brass, or brass used in more than one gun. You ask if the chamber is too tight, but maybe the other gun's chamber is too loose? You can try setting the sizing die down lower if this is possible (screwing it towards the shellholder). You may even need to turn a bit off the bottom of the die wit a lathe in some cases. You can also buy a special small base die I think they called it (I think EGW has them). Your dies may be out of spec.

4. If the case alone checks out, then seat a bullet (dummy with no powder, primer, or anything). Be sure to remove the bell when seating. Chamber check again. If there is a problem, it is probably the bullet connecting the leade. Not all leads are cut the same.

5. Then try seating deeper in increments and see if it fixes things. If it does you may simply need to shoot a different AOL in that gun (and obviously adjust the powder charge appropriately). This I think will fix your issue.

6. Some guns just struggle unless the ogive is a roundnouse. The parallell sided bullets can give problems in some leades if loaded out "too long" and sometimes that is not very long at all.

7. By the way, check how the cartridges feel in the Sig barrel (again as a chamber checker) as it may be the recoil spring that's pushing them in there and that is not reliable either.

8. If you are crimping and losing tension you may find that the expander is the wrong size. Also avoid over belling the case.

9. Finally, and as someone else will probably suggest it, you can try a Lee Factory Crimp Die (FCD). It will even partially swage your bullet down in the case if it is too large (particularly lead). Whether or not you think that is desireable is a matter of opinion, but for most of my pistol shooting at relatively short range I use them. The idea of meticulously sizing bullets to a revolver throat and having a crimp die mess up the dimensions is a different matter altgoether... but let's not start an argument on the FCD, I own and use several and as always with Lee there is a great idea in there.

If factory ammo chambers properly then your handloads are the issue.

Keep working on your loads - don't mess up the chamber. The looser the chamber the worse it will shoot.

Went the barrel route as a gauge. Sized cases hang up right out of the die but after taper crimping (no bullet)they chamber fine, factory ammo is sticky too though not all brands.

Lee Factory Crimp Dies are for rifle and Rimed cases correct? Taper crimps for cases that head space on the rim.

How many times has the brass been fired and loaded ?
Does the case enter completely into the die? Does the die touch the shell holder? are you using the correct shell holder for a 45acp. lyman #2, rcbs #3 redding and hornady #1

check the length of the brass it should not be any longer than .888"
While you have the barrel out you can check the length of the chamber. the gun is new to you there may be a slight burr in the chamber and could possibly need to be polished. is the bushing loose? Toggle link worn or sloppy?
Dave

The taper crimp should be just enough to remove the belling you did to get the bullet started straight. Too much crimp bulges the case behind the mouth and actually reduces tension. I suspect since the bullet won`t stay in a crimped case you have way over crimped your loads.
Check the COL of your load and see if the bullet is contacting the lead. I load the 185gr Sierra to 1.205" COL for my Kimber and it function fine. This is IIRC a couple hundredths longer then the data called for.

quote:

OK, so I dig out the taper crimp die figuring it may help, yup it puts on a nice taper and the cartridge mouth now measures .469” but now the bullets fall out.

If you crimped and the bullets "fall out" something is drastically wrong with your set-up. Over crimping can distort the case and may cause the bullets to be loose, BUT "Fall Out"?

You said this is a "Used" gun. Did you take it apart and clean it real good. Is it possible the previous owner left a lot of lead deposits for you to remove?

quote:

Sized cases come out .471” (O.D.) out of my Lyman dies.

Something is wrong here!

The OD of a sized case should be about .466 with no bullet seated, at least mine are with my Lee dies.