STI 1911 .22LR Conversion Kit

[B]STI .22LR 1911 Conversion Kit, Target Model[/B]
(manufactured for STI by Advantage Arms)

Feeling the pinch of high factory ammunition costs for .45ACP, but still want to get more practice or plinking time in with your 1911? One option is to buy a .22LR conversion kit. A variety of manufacturers, such as Advantage Arms, Ciener, and Kimber, sell these kits for 1911s. You can also get them for a variety of Glocks, Sig Sauers, etc. that are not 1911 designs.

I am a fan of STI 1911s and my local dealer, having sold four of them to me, knows this. When I asked about a 1911 conversion kit while picking up my second Ranger II about a year ago, he made me a good deal for the last STI branded kit he had in stock.

The STI kit has the STI logo, company name and location on the left side of the slide. It also has the "Robert Marvel, Custom Pistols" logo and a caliber notation on the right side of the slide. STI has discontinued sales of their rebranded kits, but you can still buy the equivalent from Advantage Arms.



The installation process is simple and is basically the same as removing and reassembling your current slide and frame. The only exception is that the guide rod is threaded, and turning it tightens the pin to the barrel.

1. Remove the slide from your 1911
2. Slide the conversion slide onto your government sized 1911 frame
3. Install the conversion kit slide stop
4. Retract the slide about 1/2" and tighten the guide rod using the supplied wrench and release the slide (the guide rod pushes against the slide stop to lock it against the barrel)
5. Function check the assembled pistol

The STI kit I bought is the target model, which has a two piece slide. The lower portion of the slide does the cycling. The upper portion of the slide doesn't move with the cycling, and it has the sights on top. The barrel is also fixed. Since neither the barrel nor the sights move while the action cycles, potential accuracy should be improved.

A quirk of this is that it's a little harder to do the slingshot method to chamber a round by using your whole hand over the top of the slide. Since the top doesn't move, you have to grab the rear cocking serrations with your finger and thumb and draw it back that way. This isn't a big deal for my purposes.

If you want to practice using it as a defensive pistol and have it operate more like your 1911, you could opt for a non-target model from AA. The non-target model slide is one piece, but also carries with it less potential accuracy.

Unlike a 1911, the conversion kit uses an external extractor. I have not had any issues with it. The left side of the slide has a steel insert to prevent the slide stop from damaging the aluminum slide when the slide locks back on an empty magazine. The top of the slide has lengthwise grooves running down it between the sights, which are set into dovetails. The rear sight has horizontal grooves to help reduce reflections.




As you may expect of a slide that isn't able to be factory fit to a matching frame, the back of the slide doesn't follow the exact contour of the back of the Ranger II frame I typically use with the kit. This is entirely aesthetic, though, and has no affect on functionality. The fit of slide to frame rails is good, and that's what affects function. No problems here.




Another slight oddity is that the slide stop lever seems to extend out fairly far compared to a standard 1911. This is because AA uses a two piece assembly, which has a pin that fits through a hole in the lever. When in place, it acts as a single unit, but once removed from the pistol it separates into two pieces again. You can see how far it extends in the picture above.

How does it perform? Very well. Using high velocity ammunition, as recommended by the manual, allows the slide to cycle and lock back on an empty magazine reliably. Standard velocity will fire, but it may not always have enough energy to fully cycle with the lower powered ammo.

I haven't performed any formal accuracy testing, but about 1" groups at 7-15 yards are the norm in my offhand firing. I haven't tested their 50 yard accuracy claims because my pistol range doesn't extend that far.

A couple more odds and ends per the manual - AA recommends that you chamber a round using the "slingshot" method of pulling the slide fully rearward and releasing it. Dry firing "can be done, but is not recommended."




[B]Specs:[/B]
Custom fitted foam/plastic carrying case
CNC machined 7075-T6 aluminum slide with steel breech insert
Heat treated 4140 steel .22LR barrel, recoil spring and slide stop
Fixed barrel and sights unaffected by slide movement
Last round lock open
Fits any milspec government sized 1911 frame
Adjustable target style sights
Anodized finish on aluminum parts (per Mil-A-8625 standard)
Black oxide finish on steel parts
Polymer 10 round* magazine (one included)
Cleaning kit with rod, brush, patches, and oil included
Guide rod tension wrench included
Manufacturer recommended ammunition - 40 grain,high velocity, non-hollow point
Remington Golden Bullets for plinking
CCI MiniMags or Federal Automatch for accuracy
Standard velocity may be used when using an optional reduced power recoil spring
Claimed accuracy - average group size at 50 yards is 1.6" with bulk ammo, 1.0" with match ammo such as Eley 10x when used with the reduced recoil spring.

MSRP: STI version discontinued, Advantage Arms target models are $350 for direct purchase, magazines are $25/each

*Note: as per the FAQ on the Advantage Arms website, higher capacity magazines are not available due to the manufacturer's location in California. CA apparently bans even the manufacture of "high capacity" magazines within the state.