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Keystone Accuracy

6.7K views 25 replies 6 participants last post by  colonelhogan44  
#1 ·
Just an FYI…John is guaging interest in his barreled uppers on Instagram. He uses the CMMG bolt but machines the breech in a manner that eliminates the collar. I have one and love it.
 
#3 · (Edited)
Will he be selling just the barrel or still need to send part for him to assemble or complete uppers?
Got the barrel from him in the past and wanted to purchase another 1. Was told that I would have to send my parts to him . Oh well because of that on my 3rd compass lake build.
John has a good product but buyers preference for the other.
 
#4 ·
I actually do not have any pictures of the entire rifle but here are a couple pictures of the barrel and barrel breech. Compass Lake Engineering and Keystone Accuracy do the same thing; they machine the breech face to accept the bolt without a collar. CLE uses an M261 bolt and KA uses the CMMG Bolt.

I was very close to choosing a CLE barrel/Bolt combo but I figured since I already had a couple CMMG bolts, a handful of magazines, a CMMG Bob Sled, redi-mag adapters, and S&W magazines that it made more sense to go that route. Yes, I sent him my parts (CMMG bolt, upper receiver, handguard w/barrel nut, and charging handle) but I preferred it that way because I could get the parts I wanted and it kept the overall cost down a bit. I called him and we discussed the barrel contour I wanted and I sent him my parts. A couple weeks later I received the complete assembled upper. It was quite painless.
 

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#5 ·
I actually do not have any pictures of the entire rifle but here are a couple pictures of the barrel and barrel breech. Compass Lake Engineering and Keystone Accuracy do the same thing; they machine the breech face to accept the bolt without a collar. CLE uses an M261 bolt and KA uses the CMMG Bolt.

I was very close to choosing a CLE barrel/Bolt combo but I figured since I already had a couple CMMG bolts, a handful of magazines, a CMMG Bob Sled, redi-mag adapters, and S&W magazines that it made more sense to go that route. Yes, I sent him my parts (CMMG bolt, upper receiver, handguard w/barrel nut, and charging handle) but I preferred it that way because I could get the parts I wanted and it kept the overall cost down a bit. I called him and we discussed the barrel contour I wanted and I sent him my parts. A couple weeks later I received the complete assembled upper. It was quite painless.
Erik-- I thought about one of those barrels (from Keystone) as well. That looks like some really nice machine work on the breech. Question: What, if anything, secures the CMMG "rails" to that breech? Or, when assembling the rifle do you have to juggle things (keep forward "hand" pressure on the bolt/rail assy) as you close the lower on the upper receiver?

While I don't have the skill set/equipment (I'm lacking a dividing head and milling machine) to do what Keystone does with that breech end, I did cobble my own barrel (using a Green Mountain stainless blank) and CMMG bolt combo together with some "basic" lathe machining.
 

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#6 ·
That's really nice work Triggershoe! My brother and I have been discussing doing the same thing with an Anschutz blank we got from Numrich. Are you happy with the way it shoots? Any issues?

To answer your question, there is nothing to capture the bolt from shooting off the end of the rails if you remove it from the receiver. However, you can break open the upper without the bolt shooting out the end. This is accomplished by a little screw in the side of the receiver that engages an existing notch in the side of the rail. I remove the screw while shooting then insert it when I want to open it up.
 

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#7 ·
That's really nice work Triggershoe! My brother and I have been discussing doing the same thing with an Anschutz blank we got from Numrich. Are you happy with the way it shoots? Any issues?

To answer your question, there is nothing to capture the bolt from shooting off the end of the rails if you remove it from the receiver. However, you can break open the upper without the bolt shooting out the end. This is accomplished by a little screw in the side of the receiver that engages an existing notch in the side of the rail. I remove the screw while shooting then insert it when I want to open it up.



Erik-- Yes, VERY happy with the way it shoots. I have a Leupold VX3 6.5-20EFR mounted on a 20min rail, and it shoots very well all the way out to 200, the max yardage I have shot with it. I'm using a Rock River lower with the BMA adapter and S&W "short" 10rd mags, also the Bore Buddy "anti-bounce" bolt weight. Trigger is a Tom Myers "Extreme" 2-stage, just a joy to pull on. I did have to install a reduced weight ("blue"?) hammer spring to get it to reliably cycle ANY standard velocity round. It was a bit stubborn with certain SV varieties, OK with others, but now runs all of them that I have tried with the reduced power spring. This spring didn't seem to affect anything else, no difference in accuracy noted.

As far as the KA barrel, thanks for that info on that little screw. I had wondered how KA was addressing this situation. Looks simple enough to do if one had somehow acquired one of the KA barrel/bolt setups (NOT the complete upper).
 
#10 ·
I was already infected with the CZ-19 virus so I'm immune, but the 457 is a beautiful rifle. I sold all my czech rimfires to people who would get out and use them, I hope.

I love the idea of a superlative AR22 built from the ground up for accuracy, but 'm still playing with variations with off the shelf components. I don't mind being the underfunded rube so long as I can still see what you 1%ers are doing.

I have high hopes for the barrel rigidity of the LW 10.5 inch barrel, but I'm still waiting for a stamp so I can put one together.