Uhl .22lr conversion for G17: Why a recoil booster?

[simonrichter]

I recently presented myself with a .22lr conversion kit for my G17. I used to have a Ciener, years ago, which was a simple blowback design. Now I have a Uhl system, made in Germany, and very expensive. I haven't tried it out by now, but it did strike me on the first glance that it features kind of a recoil booster. The barrel has a small hole drilled directly behind the chamber that connects with a coaxial second bore. On the breech, there is a piston that fits into the bore, so when shot, the escaping gases will drive the piston back and thus boost the backward movement of the slide.

Since normally you would want to minimize the recoil in a .22lr in order to provide for an easy-to-manipulate spring strength and a lower slide mass, I don't quite see the use in that measure...

Any suggestions or maybe even fellow owners of this somewhat exotic system?

 

[RickB]

Does it have a full steel slide? I'm not familiar with the Uhl conversion, but the old Colt .22 conversions used a form of recoil booster so that a full-profile steel slide could be used.
Modern steel-slide conversions usually split the slide into two parts, to reduce the weight of the reciprocating part to the extent that it can be cycled with normal blow-back.

 

[Chuck Dye]

Colt made a .22 conversion kit with a floating chamber to boost recoil. The intent is to better simulate the .45 for training. Likely Uhl makes the same argument.

 

[Oruglock]

It does sound like the slide might be heavy enough to warrant the extra recoil. I have an Advantage Arms kit for the Glock 17, and the slide is very light compared to the 9mm slide.

 

[simonrichter]

Yes, the slide has the normal weight. Yet why don't make the slide lighter and use a simple blowback? Or is all the effort maybe in order to preserve the original weight oft the 9mm version?

btw.: does the gas port likely have any impact on the performance?

 

[Chuck Dye]

Poking around a bit, I found a vendor web page that suggests the gadget is to make the conversion function with "normal" ammo. Given the steps I had to take getting a Kimber conversion to function on my 1911 with anything but MiniMags, I approve.

 

[DaleA]

I'd sure be interested in a range report with picture if possible after you shoot it.

 

[JN01]

Have yourself shot with Eley Subsonic, Eley Target Pistol, Federal Classic and Lapua Scoremax
and the gun is working properly ..... wonderful!

Gotta love the Google translator.

 

[simonrichter]

Quote:
Have yourself shot with Eley Subsonic, Eley Target Pistol, Federal Classic and Lapua Scoremax and the gun is working properly ..... wonderful!

Gotta love the Google translator.

Indeed, the muzzle energy must be pretty low since you ought to be able to shoot yourself with different brands of ammo in a row...

 

[AKexpat]

@Chuck Dye

Given the steps I had to take getting a Kimber conversion to function on my 1911 with anything but MiniMags, I approve.

This is a bit off topic, but your Kimber should have functioned with standard velocity rounds. There is not much difference between HP and SV rounds when it comes to cycling a round in a 1911 .22 conversion kit except the mainspring strength. If you want to have the best of both worlds (.45 and .22 with the same pistol) replace the mainspring (23 lbs) with a Wolff 19 lb. spring. It will still function admirably.

I have an AMT Hardballer that runs .22 and .45 ACP with all manner of factory loads in both calibers with a 19# spring with the Ciener .22 kit. Standard .45 ACP mainspring is 23# which is too much.

My newest project is an Oly Arms frame with a 19# mainspring with a 1994 era Ciener .22 LR conversion kit. It runs with Rem Subsonics, CCI MiniMags, and Yellow Jackets with no problem.

 

[simonrichter]

Here is a video review of the Uhl system: https://www.youtube.com/watch?v=7ZKxjV-gWSA

 

[Snyper]

Yet why don't make the slide lighter and use a simple blowback

It's hard to make it lighter when they have to maintain certain dimensions, and a recoil booster increases reliability no matter what load is used

 

[simonrichter]

I have spent some range time with the conversion in the meantime and it indeed functioned flawlessly with any kind of bulk ammo, regardless whether HV or standard loads...

The gas port-and-piston-system is a little messy, of course, but worth the effort.

It also makes (as explained in the video) the recoil a little stronger (actually surprisingly strong for a full-size, full-weight handgun in .22). The 9mm still kicks harder, of course, but it has some use for training with .22lr in any case...