10mm reloading too deeply?

[wiiawiwb]

I am reloading my first 10mm round and made up a dummy one. I am using new Starline brass and MBC .401 diameter 170 gr SWC:

http://missouribullet.com/details.php?prodId=218&category=20&secondary=11&keywords=

Lyman's 49 shows maximum OAL of 1.260. I've seated the bullet in the middle so that the OAL is 1.259. It is seated deeper than I thought it would be. I thought it would end up midway between A and B. It's ending up almost to A. For comparison purpose, on the left is a factory round from Hornady, 180 gr XTP and it measures 1.252. The reloaded round meets the barrel plunk test and feeds into my Glock 40 just fine.

Does the seating depth look correct?

 

[Hondo 60]

Does it pass the plunk test when seated to "B"?

It it were me, that's where I'd be seating it to.

 

[Robert101]

maybe its the angle of the pic but the reloaded round on the right looks like the brass case is longer. Check it with calipers - this maybe contributing to your issue. 1.260 is Max OAL for 10MM - I agree. The reloaded round does have the bullet set deep into the case but there is room left at the upper edge. If it fits fine into the chamber you should be fine.

 

[billybob44]

The reloaded round meets the barrel plunk test and feeds into my Glock 40 just fine.

Hondo is right+you have answered your own question..

 

[rcmodel]

It should end up at A.

Seated to B, the full dimeter bullet shank will most likely hit the rifling before the round is fully chambered.

The SAAMI drawing shown in the Lyman manual shows a MAX length that will fit in a 10mm magazine.

Unless you are using the same exact bullet they used, you can't base your seating depth on the SAAMI Max length shown.

And your MB isn't an exact match.

rc

 

[dragon813gt]

Set your OAL using the plunk test. W/ that design you're going to have to seat deep because of the shoulder. Load it long and see if passes plunk test. If it doesn't seat it a little deeper and repeat. Unless you're using the exact bullet and firearm in the manuals the OAL isn't the end all be all.

 

[wiiawiwb]

If it were seated to B it would be a much, much longer than OAL. I didn't stop there and do the plunk test because I was trying to get it to or below OAL.

Not quite sure why the OAL has it seated at the rim of A but that is where it is.