10mm bulge. How much is too much?

[JONWILL]

Picked up a Colt Delta earlier this year

I got some PPU ammo mainly for the brass to reload. It isn’t hot but definitely more than the usual 40S&W level that some factory ammo is loaded to

I don’t have a chronograph but did buy some SIG Elite ammo to compare recoil.

I use Bluedot and a 180 grain XTP bullet

I started the powder load at 9.5 and increased .2 grains until I made it to 11.0.

I measure the powder in each round by hand

At 10.1 I noticed the slightest bulge in the base

I have seen pictures of the “Glock Smile” and it is no where near that

It is definitely more powerful than the SIG load

Would you back off or stay at that load? I don’t reload the brass that has the bulge but throw them out

 

[ATLDave]

I would go in a different direction.

First, my experience with PPU 10mm brass is that it is prone to setback/poor neck tension, particularly after multiple loadings. I used to use a lot of it, and now I rarely do. Just suck it up and buy some Starline, which is the gold standard.

Second, I have read various things that makes me wary of Blue Dot in this application. There are many powders that seem to have less in the way of twitchiness/non-linear pressure in the 10mm load range.

Third, Colt Deltas do not have the greatest chamber support at the base of the brass. If you're getting noticeable bulging, I'd back off.

When I was first getting into 10mm, I found a lot of helpful information at this dedicated 10mm forum http://10mm-firearms.com

 

[BigBore44]

Ok. Since this got brought up again, I have to ask. What is so special about the CDE? It doesn’t have a heavy barrel, fully supported chamber, or ambidextrous thumb safety. Yet it’s $1000. My RIA Tac II has all those features and it’s $500-$600. I know it sounds like I’m knocking the CDE. I’m not. It’s just a question. Is the name really worth the extra $400-$500? Or is there something else that is?

 

[ATLDave]

Well, the CDE was the first of the 10mm 1911's (even if the current designs are somewhat different in features than the original), it's generally made to a nice standard of workmanship, and it comes with a dancing pony. That always costs a little more.

 

[BigBore44]

So it’s the name. I’ll give you that name equals higher resale value. But I plan on keeping mine. It just seems like a $1000 pistol would have more features. Especially features that actually make the gun better. Like at the least, a fully supported chamber.