Monday, January 29, 2018

Boolit test

I tested 50 of these in my rebuilt Springfield

https://www.federalpremium.com/ammunition/handgun/caliber/45-auto

Disaster.

Ok, I am using McCormick mags, and they are pretty old.  But with 4 fresh mags the bullets failed to feed on the first round.  It was like I had loaded 8 rounds into the mag.

"NO!  NOT FOUR!"

Yup.  That's what I get for weird experiments.

The tip gets stuck on the feed ramp.  Which also might really mean that the rim is stuck at the breech face and can't slide up under the extractor hook.

(Gunsmith tip:  When you get FTFs like this, check the extractor before you start breaking out the Dremel to 'polish' the feed ramp.  It's hard to add metal to the feedramp after you drum sanded it off...)

So, what else could it be?

The Over All Length on these bullets seem shorter, and that reverse Ogive shape is changing SOME of the dimensions in operations.

The mags are old, the springs and followers might be getting tired.

"If you are not going to shoot that weird bullet type a lot, T-Bolt, then why bother to fix it if the gun runs HST and hardball 100%, just fine."

Maybe this flaw is communicating with me.  It fails easy on the semi-wadcutter now but won't start failing with the full metal jacket for 500 more rounds.  This guy is giving me a heads up early.

"Could it be the feed lips?"

It could be.  The feed lips spreading could change where the mad 'lets go' of the cartridge when the slide slips it out.  One of the nice things about McCormick is the metal is a thicker and stiffer gauge.  That doesn't mean they aren't spreading, it's only less likely.

"If the follower is toast, T-Bolt, can you even get replacement ones?"

Well...  The followers are harder the find.  The springs are easy.  If I can't find the followers for sale, I'll just hurry up and get new mags.  Mags cost $23.  The spring alone costs $10.  The magazines are cheap enough at that price point to maybe not risk too much maintenance on them.

-

 So assuming good mags, and I wanted to shoot a LOT of these lighter, funny-shaped, .45s?  Like if it was a bullseye gun.  I'd have to place with the extractor tension to make it lighter to let the rim up under the extractor more readily.  Long before I'd ever dream of messing what is now a very good frame and barrel ramp.


4 comments:

Sdv1949 said...

You need a steeper angle feed ramp for SWCs. Several of mine have had to be recut.

HTH

Will said...

If you down-load the mag, does it feed?
Check the rim dimensions of that brass. Might be out of spec.
Slide moves smoothly?
Try other mag brands/styles. For me, last resort would be Wilson, as they are designed to release the cartridge early, to fix/bandaid loading problems. They're not a controlled feed design, like JMB intended.
If all else fails, try a heavier recoil spring. (My benchmark is a steel frame Officers Model that will feed empty cases, but they run 22 lbs original, and 24 lb Wolfe.)

Oh, forgot an important check for this problem! Measure OAL before and after loading attempt. Bullet setback will absolutely kill the loading cycle of Gov Mods. If it's more than a few thou, you have an ammo problem.

ASM826 said...

It's the feed ramp angle and finish. The same gunsmith that can correctly set your sear and hammer engagement can fix this. When he's done, you should be able to hand cycle empty cases. I shoot cast semi-wadcutters, they look very similar to the picture you showed, and that is what it took to make them feed reliably.

New Jovian Thunderbolt said...

Already done the feed ramp and finish. Not optimized for SWC obviously.