Shorty9-4046TSW-357 SIG

[JohnHL]

Just took a look at a couple of fired brass from the SW40 and the 357 SIG barrels. Firing pin marks are different even though its the same for both barrels. The 40 round looks marked all the way around, unlike the SIG round.
Interesting.

Hey, Matt!

When I see a firing pin drag on a primer (as in your first picture), I must wonder if the higher recoil velocity of the cartridge is a sign that the empty shell is bumping against the firing pin during extraction/ejection.

Can the higher slide velocity generated by the higher pressure cartridge (357Sig vs. 40s&w) exceed the firing pin spring's ability to retract the pin.

I think it is a mistake to go to the higher pressure and velocity round while staying with the lower pressure round's recoil, main, and sometimes firing pin springs.

In the second pic, I would think the differences in the case markings are the result of differences in the finish of the two chambers.

Unless I'm missing something...

And many have said that I definitely am!

John

 

[JohnHL]

Interesting job, makes me wonder about the feasibility of making my 4053 into a dual caliber gun.

It can be done, but on the large frame 4053, the only practical option is 10mm.

Many have done it, but it can be hard on the alloy frame.

John

 

[Heymatt]

So, what size recoil spring rate would you suggest as a starting point? Factory rate shown on Wolf’s site is 17lb, with 18,20 and 22 available.
A calibration pack includes all 4 with extra power firing pin springs.

 

[BAM-BAM]

Interesting ....... I own a couple of Shorty-9s and one is a primary concealed carry piece when I want more than the 7/8+1 in a 39xx series gun.

MY FrankenSmiths go the other way a 915 upper fitted to a 69xx frame.....longer slide conceals nicely IWB in a Sparks Summer Special; short butt with modified mag base doesn't print; gun paired with 1/2 15rd mags w/ +2 adaptors for reloads.

 

[JohnHL]

So, what size recoil spring rate would you suggest as a starting point? Factory rate shown on Wolf’s site is 17lb, with 18,20 and 22 available.
A calibration pack includes all 4 with extra power firing pin springs.

I would start with an extra power firing pin spring to help the firing pin to retract faster.

On my 357Sig conversions, while 20lb. is standard hammer spring for the 40s&w, I went up to the maximum, 23lb. to keep the slide closed longer and reduce frame battering.

Pretty much the same for the recoil spring.
17lb. is standard.
I went up to 22lb.

Helps tame the recoil and reduces battering.

John

 

[Heymatt]

Update on this one.
It was nice to have the ability to swap top ends around to have three calibers on the same frame.
Just didn’t seem fair for the PC9 to have to share, so.
Now I have the PC9 slide dedicated to it’s own 4046 TSW frame with a Red dot. The Sig barrel will have it’s own 4046 TSW frame with a PC cut slide from Guzzitaco.
Pics of course

 

[Heymatt]

Finally got the 357 conversion to the range with the increased power springs. No more double hits on the primers. Still a hoot and a half to shoot!
Guy at the range next to me was shooting 9mm. I let loose some of the 357 SIG rounds and there was a noticeable pause in his routine
Switched over to the 457 to confirm function and called it a day.

 

[Tntcwg3]

Nice to see a project come together!

 

[doubletapp357]

This is what I love to see! Im a huge 357 SIG fan! This looks sweet!