M&p 40 problems.

[gdouthit]

I'm having this FTF with my reloads

All brass is sized and belled. I'm using 155gr SWC's with 6.8 grains of silhouette. Seated to 1.125.

 

[Dawico]

You aren't crimping enough to remove the bell. You don't need much crimp but you do need to fully remove the bell.

 

[gdouthit]

Crimped down to .419~.420. Still have one hang up every now and then but solved the bulk of it.

Idk why now but iv never had this problem before. Haven't even adjusted the dies in 800 rounds!

 

[Dawico]

The amount of crimp is determined by the case length. If this is newer brass (shorter) it isn't going into the die far enough to get the bell removed.

I crimp so the case just has a hair of an inward bend to it. This makes sure the shorter brass is getting the bell removed fully and any cases longer are getting a hint of an inward bend.

The term "crimp" really isn't accurate as the round doesn't need it. There should be plenty of neck tension to keep the bullet from moving.

 

[rsayloriii]

Agreed... the belling isn't being fully removed on all cases. I'd also try to limit the belling to the least possible. Shouldn't need much; just enough to get the bullet started without shaving the bullet during seating.

sent from deep space

 

[gdouthit]

Thanks guys. I'll back my expander out and tweak my seating die a little more.

Have y'all tried any ram shot powders? I like silhouette so far. I was going to try TAC in my ar. It seems like ram shot is the only powder that my LGS can keep in stock.

 

[Dawico]

Agreed... the belling isn't being fully removed on all cases. I'd also try to limit the belling to the least possible. Shouldn't need much; just enough to get the bullet started without shaving the bullet during seating.

sent from deep space

Good point. The bell does seem a little excessive. That will shorten the case life.

 

[Dawico]

Thanks guys. I'll back my expander out and tweak my seating die a little more.

Have y'all tried any ram shot powders? I like silhouette so far. I was going to try TAC in my ar. It seems like ram shot is the only powder that my LGS can keep in stock.

I have tried it but see it very seldom. I don't really look for it either though.