10-4. Just want to be sure folks understand that this barrel was purpose designed and not the typical plug n play AR barrel.
Too many good rail options out there. Looking for picatinny, keymod or mlok?
Ultimate suppressed upper?
- Thread starter DarthVader
- Start date
Too many good rail options out there. Looking for picatinny, keymod or mlok?
More info here on the barrel. The author of the thread snagged one of only a few that were overruns from the original PD order.
http://www.m4carbine.net/showthread.php?t=178402
http://www.m4carbine.net/showthread.php?t=178402
Keymod or m-lok. I have one of each on different rifles right now but can't decide which I like better. I'm leaning towards a M-lok frail from MI.
https://www.midwestindustriesinc.com/index.cfm?fuseaction=category.display&category_ID=1266
Most importantly I want the rail to end right where the barrel ends.
Don't want to recess the can.
That 10inch rail looks just about right.
How much of the 11.5" is actually recessed into the receiver?
For a flush fit to barrel shoulder, you need about 3/4" offset. In other words, 10.75" rail is the max for an 11.5" barrel. I'll be running a 10" rail.
The only one that I know for certain, is the KAC URX II, III & 3.1 midlength. I believe that the KMR is actually a little over 10". I actually prefer a little shorter. My URX 3.1 upper would not allow use of the AAC brake mount. Because of the difference in design between it and the blackout / brakeout mounts, I couldn't use the Brake on my upper. But for a direct thread like the Grunt, I'm not sure it would matter.
Well I'm sure you'll get yours assemebeld before I do. So I'll wait and see what you're looks like lol.
The MI rail is 10.5 so I may go with that and call it a day.
Maybe. The barrel won't be here for a few weeks. I should have it done by the end of February.
That'll be before me lol. This prolly won't get finished for another year. (Finished including the can being pinned)
Solid choice. Sionics actually uses a lot of MI rails on their complete uppers and rifles.
I'm going to use a blem upper from BCM. They have finally worked through all of their old stock and the current blems are the BCM4 receivers. I've used a lot of BCM blem uppers and have rarely found a flaw. Still debating on the rail. Probably going to use a KMR-A, but not fully decided yet.
I've used two of the BCM blem uppers before and they were both def blems but just cosmetic. They have worked fine with no issues.
Just need a gas tube and block. (Plus the can @DoglegArms )
Yeah, it's the luck of the draw with blems. The ones I've had were really, really minor. Like a spec in the anodizing. But I really like the BCM4 uppers because they have a tight fit to the barrel extension. And for $80, they're hard to beat.
I have the same in 15". To tell the truth I wish it was a little less thin, but it's been solid. I shoot with a sling, and haven't noticed any deflection of the front sight at 100 yards.
The lightweight model just doesn't have the complete top rail, just a couple inches in the front and back. Everything else is the same.
I am curious why not make a "press fit" style gas block with a reduced inlet port?
I know pressing the gas block on would not be a home job for many, but using a bearing heater or hot plate to heat the gas block before installing would create a tight seal once installed/cooled and eliminate the possibility of gas leaks around the block.
This would keep barrel options open and allow you to go back to normal gas if you wanted (if you were able to get the gas block back off that is....)
Below is a CAD (crappy ass drawing) of what I am trying to explain.
Edit: It would possibly work as a non press fit, but I just feel it would has gas leakes around it otherwise...
I know pressing the gas block on would not be a home job for many, but using a bearing heater or hot plate to heat the gas block before installing would create a tight seal once installed/cooled and eliminate the possibility of gas leaks around the block.
This would keep barrel options open and allow you to go back to normal gas if you wanted (if you were able to get the gas block back off that is....)
Below is a CAD (crappy ass drawing) of what I am trying to explain.
Edit: It would possibly work as a non press fit, but I just feel it would has gas leakes around it otherwise...
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