Yeah I ran most of the popular ar alternate calibers plus a few wildcats with good success with both the ar and IRM recoil systems in the m11 beta upper. Unless there is a big difference in bolt weight between the ar15/m16 bolt carriers and Richards proprietary bolt carriers I think most calibers will run. I haven't had time to play with the max15 uppers much lately due to spending my time building the prototype for its big brother.
MAX 10-15/11-15 Caliber Mod Thread
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Yeah I ran most of the popular ar alternate calibers plus a few wildcats with good success with both the ar and IRM recoil systems in the m11 beta upper. Unless there is a big difference in bolt weight between the ar15/m16 bolt carriers and Richards proprietary bolt carriers I think most calibers will run. I haven't had time to play with the max15 uppers much lately due to spending my time building the prototype for its big brother.
IF Sprinco is the place to go, can someone please point me to the product there? I looked all over their site and don't see any spring reference that I could find which leads me to believe it is the correct one for the Max 11/15 IR system. TY
Definitely call Lage MFG for the heavy recoil spring. The IRM heavy spring is not mentioned in the Max-11/15 manual. I'm not sure if it is even used on the Max-11/15.
It is mentioned in the Max-11A1/15 manual for use on the A1 version.
It is mentioned in the Max-11A1/15 manual for use on the A1 version.
A&S Conversions
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Will open a new thread so as not to clutter this one.
Scott
Scott
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m11stuff@hotmail.com
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The MAX-10/15 and MAX-11A1/15 do not use AR springs. Both use the IRM spring that we provide.
Well this is getting old. Another OOB discharge. Whole new barrel, bolt, firing pin and cam pin. Sorry about the video quality. I tried to brighten it up. maybe it will show enough for someone to have an idea. I did about 25 single shot rounds to get the gas setting correct. This was the 2nd mag about half way through. Barrel is clear, no round stuck in it.
I ensured the barrel was lined up properly and the barrel nut very tight. Passed go/no-go gauges. WTF.... This is really E'ffing up my expensive Max15 upper.
If you set the youtube playback to 25% it seems pretty evident that the bolt did not completely seat before it fired. All previous shots seem to show the bolt much more forward.
Here is what I don't understand. In a standard full auto ar15 BCG, the bolt it fully locked and rotated before the auto sear releases the hammer. In the MAX, the firing pin protrudes when the bolt is pushed all the way back however it still needs to rotate to be fully locked. Seems like a small amount of delay should be present to ensure it is locked. Obviously the system works as designed with so many others have great success. Just trying to understand hot this could be happening.
Thanks for any insight.
https://youtu.be/BhQS_0vg34Y
I ensured the barrel was lined up properly and the barrel nut very tight. Passed go/no-go gauges. WTF.... This is really E'ffing up my expensive Max15 upper.
If you set the youtube playback to 25% it seems pretty evident that the bolt did not completely seat before it fired. All previous shots seem to show the bolt much more forward.
Here is what I don't understand. In a standard full auto ar15 BCG, the bolt it fully locked and rotated before the auto sear releases the hammer. In the MAX, the firing pin protrudes when the bolt is pushed all the way back however it still needs to rotate to be fully locked. Seems like a small amount of delay should be present to ensure it is locked. Obviously the system works as designed with so many others have great success. Just trying to understand hot this could be happening.
Thanks for any insight.
https://youtu.be/BhQS_0vg34Y
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I can’t say for sure, but I suspect bad ammo. This is what I think happened. The bolt flew forward and completely seated because the firing pin must have struck the primer (the firing pin doesn't protrude from the bolt until the bolt is closed). The round did not immediately fire (due to a bad primer?). The bolt appears to (mechanically?) bounce back and as the bolt moves backwards, the primer then fires the round. I’ve tampered with your video and you can see it here:
https://www.youtube.com/watch?v=8y67mvyeXaI
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This is almost true. In a M16 the bolt is fully locked when the BCG is at the tail end of its forward motion when the auto sear trips. Remove your ar15 upper from your lower and slowly push the BCG forward while observing the bolt rotation. You'll notice that the bolt is fully rotated and the BCG will still move forward ~1/16". It's at this last bit of forward movement the auto sear in an M16 is tripped.
As far as I know the Max15 works much the same way. (I do not own one and have never inspected one so take this with a grain of salt). The firing pin is attached to the BCG and moves directly with it. The firing pin only protrudes through the bolt face at the very last ~1/16" movement of the BCG. The firing pin is only exposed AFTER the bolt has fully rotated into the locked position.
As far as what is causing your OOB discharge, I'm not sure. Is it possible your bolt face is recessed slightly more then a normal 5.56 bolt? Did you do anything with the firing pin that would cause it to protrude more?
Thanks for the insight guys. Eric, I slowed down the original video and I can see what you are explaining. Seems the bolt does go all the way forward. Can an ar BCG recoil mechanically like that? Is that normal? Perhaps the barrel/bolt alignment isn't quite right and allows it to bounce back/unlock mechanically? If it is bad ammo with a slow primer, then I am screwed as I have had 3 bad rounds out of a 60 that I have pulled out of a can of a thousand or so. I suppose I can relegate these rounds to my Ak semi's.
Quigly, thanks for the clarification. I had the first OOB discharge using the 7.62 bolt and the oem MAX firing pin. I did compare it to the replacement pin I got and the MAX pin was a hair shorter. Like almost immeasurably.
So, perhaps it is an ammo issue and this is why I am not seeing an issue running the 5.56 setup. However, I don't think the bolt should "bounce unlock" unless there is some alignment issue between the bolt/barrel or an excessive amount of play in the bolt/cam pin in the upper that allows it to rotate when it shouldn't.
I am wondering about the cam pin detent in the upper. It seems to be excessively long. Like it starts too soon. When manipulating the bolt with the upper disassembled, it seems that the detent would allow the rotation of the bolt way sooner that it would ever need. So if the bolt met some resistance or wasn't aligned perfectly with the barrel extension that it would allow it to rotate, move backwards and expose the firing pin before being seated/locked
Anyway, I have yet another 7.62 bolt coming with a couple new firing pins. I am also going to install a roller cam pin, resurface the inside of the upper and possibly re-profile cam pin detent to ensure it will only allow rotation once seated and not before. I will also pick up some better spec brass ammo for the next go.
Critiques, advice welcome. More to come.
Quigly, thanks for the clarification. I had the first OOB discharge using the 7.62 bolt and the oem MAX firing pin. I did compare it to the replacement pin I got and the MAX pin was a hair shorter. Like almost immeasurably.
So, perhaps it is an ammo issue and this is why I am not seeing an issue running the 5.56 setup. However, I don't think the bolt should "bounce unlock" unless there is some alignment issue between the bolt/barrel or an excessive amount of play in the bolt/cam pin in the upper that allows it to rotate when it shouldn't.
I am wondering about the cam pin detent in the upper. It seems to be excessively long. Like it starts too soon. When manipulating the bolt with the upper disassembled, it seems that the detent would allow the rotation of the bolt way sooner that it would ever need. So if the bolt met some resistance or wasn't aligned perfectly with the barrel extension that it would allow it to rotate, move backwards and expose the firing pin before being seated/locked
Anyway, I have yet another 7.62 bolt coming with a couple new firing pins. I am also going to install a roller cam pin, resurface the inside of the upper and possibly re-profile cam pin detent to ensure it will only allow rotation once seated and not before. I will also pick up some better spec brass ammo for the next go.
Critiques, advice welcome. More to come.
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m11stuff@hotmail.com
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If you are concerned about wear and tear or inadvertent damage to the upper, you can send it back when you are finished experimenting and we will swap out the left side for free. We are sorry that you are experiencing this trouble trying to get 7.62x39 to work for you but we are also interested to see how this works out.
Is it possible the issue is hard primers and/or delayed primer ignition?
Is it possible the issue is hard primers and/or delayed primer ignition?
The slow motion video is interesting. I understand bolt bounce on a .22 but I don’t see how a rotating bolt can bounce. Is it possible that this is a powder issue? Is it possible that the primer is igniting enough of the powder to start the bullet down the barrel and enough gas pressure to start unlocking the bolt and then the remainder of the powder is flashing in sort of a perverse hang fire? I’ve never seen this with smokeless powder, so I’m not even sure it is possible. Just musings of an armchair ballistics guru.
m11stuff@hotmail.com
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If you would like to, we can send you our extra power spring to try. If it is hard primers, that should help resolve it. No charge, just e-mail us.
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