The macho answer is "You're gonna hate it, but the more you hate it, the more you will love it"

If you run moderate defensive loads in the 10mm P220, the recoil will be comparable to that of a 45ACP.

The 500 S&W Magnum is a Howitzer with a grip. You should see the rounds I fired in Ohio a few months ago.

You mean these Scott?




Here's the REAL new GGI project...

Stu,

Yep that's them. Shooting one of those rounds felt like I was holding a steel pipe while somebody my size whacked the end with a 30 lb sledge hammer. Now that's recoil.

yeah, the second to last pic shows it in recoil

quote:

Originally posted by braillediver:
I’ve never shot a 10mm. I’ve shot 9mm, .40 s+w, .357 sig, .38 and .357 magnum.

If the guns are similar, like the SIG P220/226/229, looking at the "power factor" (PF) of the different loads is a pretty good way of evaluating felt recoil. PF is a momentum-based figure that is calculated by multiplying bullet weight in grains by velocity in feet per second and dividing by 1000 (the last just produces more manageable numbers). Gun weights and recoil spring stiffness also affect felt recoil, but PF gives a pretty good baseline comparison.

The following are some PF figures for common SIGs and ammunition based on my velocity measurements:

P226, 9mm, 124 gr. FMJ, CCI Blazer: 137
P226, 9mm, 124 gr. +P JHP, Speer Gold Dot: 150
P226, 9mm, 124 gr. JHP, Gold Dot: 138
P229, 9mm, 115 gr. FMJ Blazer: 133
P229, 9mm, 124 gr. +P JHP, Gold Dot: 150

P226, 357 SIG, 125 gr. Gold Dot, standard (not limited penetration): 174
P229, 357 SIG, 125 gr. Gold Dot, standard: 168
P226, 357 SIG, 125 gr. Winchester SXT: 170
P229, 357 SIG, 125 gr. Winchester SXT: 166
P239, 357 SIG, 124 gr. Winchester SXT: 162

P226, 40 S&W, 155 gr. Gold Dot: 185
P229, 40 S&W, 155 gr. Gold Dot: 178
P229, 40 S&W, 165 gr. TMJ Blazer: 180

P220, 45 ACP, 230 gr. FMJ Blazer: 185
P220, 45 ACP, 200 gr. +P Gold Dot: 218
P220, 45 ACP, 230 gr. Gold Dot: 182

Factory data for 10mm (I'm not sure all these loads are still available)

180 gr. Hi-Shok and Hydra-Shok JHP Federal (5"): 185
180 gr. FMJ Federal (5"): 191
175 gr. Silvertip JHP Winchester (5.5"): 226
155 gr. Gold Dot JHP, Double Tap load (4.6"): 229
180 gr. Gold Dot JHP, Double Tap load (4.6"): 234

Note that the factory figures are claimed muzzle velocity as compared to my instrument velocities at 10 feet. Also, Glocks (which Double Tap uses) tend to produce higher velocities from the same barrel lengths than SIGs. Further, Winchester and Federal use 5.5 and 5-inch barrels for their data, and I would expect velocities from 4.4" barrels to run at least 50-100 fps slower.

After all that, I agree with Flork's statement, "If you run moderate defensive loads in the 10mm P220, the recoil will be comparable to that of a 45ACP."

The Gold Dot 200 +P 45 ACP load has the most recoil of any round I've fired from my SIG pistols. Its recoil was definitely noticeable from a P220R, but hardly unmanageable. It's not too far behind any of the 10mm stuff, except the DT 180 grain. Also, the GGI 10mm conversion will use a steel-framed 220ST and that will help tame recoil some.

FYI for our Southern California SF members:
Here's a 220ST for sale on CalGuns.net:
220ST on CalGuns

quote:

Originally posted by Grayguns:
We've seen too many prematurely worn P229's in 357 SIG or .40 to consider an alloy 10 a sound idea, knowing what we know so far.

-Bruce

Interesting, first I've heard of this.

Can you give some more details. Feel free to e-mail me (is in my profile) if you don't want a thread drift.

Thanks
cc

I just bought a NIB P220ST for the express purpose of sending it to GGI for the 10mm conversion. I'm not a 10mm fanatic but I am a fan. Back when Sig said they weren't going to come out with a 10mm Revolution, I bought a Kimber 10mm. But that just whetted my appetite and I've been looking for another 10 that I could buy in CA (but not a Glock!). When Bruce announced that he was working on a P220 conversion, it gave me hope that there might be one more semi-auto out there that I could get passionate about. It costs more than I expected but after reading what GGI is putting into the conversion, I feel that I'll be getting my money's worth and getting a pistol that is designed to be a 10mm and not just a .45 that can chamber a 10mm cartridge. I'm not the sort of person to be an "early adopter" but I trust Bruce even though I don't know him. He's got a reputation in the industry that he would never jeopardize just for the sake of making money by meeting a fickle demand. In the not-too-distant future I'll hold a 10mm Sig Classic series pistol in my hands and think that I'm holding something special. And then I'm going to point it down range, squeeze off that first shot, and remove all doubt.

quote:

Originally posted by sjtill:
FYI for our Southern California SF members:
Here's a 220ST for sale on CalGuns.net:
220ST on CalGuns

Also, Turner's had 9 220STs in their warehouse when I walked in their door this evening - now they only have 8.

I deem this post worthless without 10mm 220ST photos......

Scott when do we get to see pictures of the R and D prototype?

Foshizle. Time to start hunting for a 220ST...

Bruce, Flork & Co., you guys never cease to amaze us! Congratulations for doing this project! Looking forward to seeing your development progress. Guess all of us dealers will be selling more 220ST Elites now! My impression from reading this thread is 220 Carry ST Elite was not deemed suitable for this conversion for some reason?

45R,

No photos until we have it finished and ready to test fire.

Ordnance Outsellers,
The Carry is way too short of a slide which is also too light to be able to handle the recoil of the 10mm cartridge. If we made a short slide version the recoil would beat the living snot out of the frame unless we sprung the slide with a 40lb recoil spring.......

Flork, figured it wasn't overlooked and force/velocity of recoil required full size. Thanks for clarification!

I'm seriously interested. E-mail sent.

Or for $510 I could get a Glock 10mm.

quote:

Originally posted by Flork:
45R,

No photos until we have it finished and ready to test fire.

Flork-

When you have one finished and ready to test fire...make sure I'm around for the gun porn photos....

Hey for those of us who already have a ST and want to be able to shoot both the 45ACP and 10mm does the conversion change the frame to shoot 10mm only or can we still shoot 45ACP if we have another slide/barrel combo.

Serious question: How does Glock make their short slide G-29 able to handle the 10mm without any problems? Where are the critical differences between the way the Glock makes their frames and slides versus the Sig frame and slides such that the alloy frames of the full size 220 and the short slides of the 220 Carry are not up to par enough to handle the 10mm? Are the aluminum rails of the Sigs versus the steel rail tabs of the Glock the critical difference there? Just curious. Thanks!

Anyone have a suggestion on where to find a P220 Elite Stainless? (for this project)

The Supermatch looks great too, but has the AL frame - does the longer slide help in that regard?

I've been looking with no luck; idears welcome.

quote:

for $510 I could get a Glock 10mm.

...and that would do what toward obtaining a 10mm sig?

quote:

Where are the critical differences between the way the Glock makes their frames and slides

the glock's frames flex