Pressures of a 10mm conversion and Decisions, Decisions…

[dandean316]

I was thinking of getting my Para Ordnance 16.40 LDA converted to 10mm. The concern I had was with the higher pressures of 10mm, will this cause stress on the frame and shorten the life of the gun? I am concerned the Para .40 frames are not setup for 10mm and although you can do the conversion, is it wise? From what I read the Colt frames are strengthened to accept the higher pressures.

I am in a trade deal right now trading my 16.40 and money for a Colt 10mm. The guy I’m trading has several unfired Colt 10mm’s and I basically get my pick. Thing is, I will end up trading my barely fired 16.40 LDA and spending an additional $300 to $900 extra for the Colt.

But then I thought, why not just get the Para converted?

Or maybe I should just sell the LDA and get the P16 converted. Or maybe I should just get a new .45.

Any comments are appreciated.

 

[Sean Smith]

Well, the pressures aren't what put stress on the frame... the pressure is contained in the barrel. And 10mm pressure isn't much higher than .40 S&W pressure... 37,500 psi vs. 35,000 psi. The reason 10mm gets more velocity than .40 S&W is mainly due to case capacity... IIRC a 10mm case loaded with a 180gr bullet has 50% more case capacity than a .40 S&W case loaded with a 180gr bullet. Can you say "more gas"?

Your main concern is how well the frame holds up to the increased RECOIL forces, which can be substantially higher than those in .40 S&W (going from 400 to 600+ foot-pounds will do that). Delta Elite frames WEREN'T reinforced... they had metal REMOVED to prevent stress cracks. And while they are good forged steel, there is nothing magical about Colt frames, either. My experience with Para-Ordnance is pretty bad, so I wouldn't use them for ANYTHING, but there is nothing per se wrong with converting a .40 S&W 1911 to 10mm Auto, since a .40 S&W 1911 (unlike other .40 S&W gun designs) is basically identical to a 10mm 1911, except that the chamber is shorter.

You can see the frame modification made to Delta Elites here: http://www.geocities.com/mr_motorhead/10tech.html#delta

(Many later .45 ACP 1911s had the frame modification, too).