My cheapo 300BLK

[rainman64]

How do you like the plum crazy lower? Have you had any issues with it? I am looking at one for my first ar-15 build. Plan on getting one this weekend.

[CJ]

Well I trimmed a spare buffer spring down to just a hair under 10". This is just shorter then the minimum carbine length spec, which is 10 1/16". It's about a 1/2" shorter then the two carbine springs I measured.

I'm still contemplating opening the port. The largest reamer I have on hand is .137", and I might just use it

I would hold off on that until you test it first.

[GAP]

How do you like the plum crazy lower? Have you had any issues with it? I am looking at one for my first ar-15 build. Plan on getting one this weekend.

I like it. I havn't had a problem with it yet. The trigger on it is pretty nice and it's a great value.

[GAP]

I would hold off on that until you test it first.

I know! I just want it to work now, and not have to make numerous trips to the range. But that's the caveat of building with non plug and play components.

[gat0r]

considering where everyone else is at successfully, going to .156 would cause more issues for you using subsonics

[gat0r]

are you using w/ your suppressor?
this is why i use the low setting.

i dont mess w/ shooting subsonics w/o can

i thought the 300blk was designed to shoot subsonics w/o use of adj. gas block when not using suppressors

[CJ]

are you using w/ your suppressor?
this is why i use the low setting.

i dont mess w/ shooting subsonics w/o can

i thought the 300blk was designed to shoot subsonics w/o use of adj. gas block when not using suppressors

if the gas block is in the pistol location. From my understanding carbine location barrels require a suppressor to cycle subs.

[bigshoe]

From my understanding carbine location barrels require a suppressor to cycle subs.

This is what the guy at Wilson Combat told me yesterday on the phone.

[GAP]

Well, hopefully i'll be able to test out my re-tuned system on Sunday. I've read posts on various boards (googling), and some have had success with 16" barrels with carbine gas systems cycling factory remington subsonic loads. I wont be heart broken if I dont get subs to cycle though.

[GAP]

Well, this thing just doesn't want to cycle. The gas port is now .133", the buffer is 1.9oz, and I shortened the buffer spring an inch. It still wont even cycle factory 115gr Remington. I'm thinking I need to just ditch the Adams Arms piston, and go DI with an adjustable gas block. Thoughts?

[CJ]

Well, this thing just doesn't want to cycle. The gas port is now .133", the buffer is 1.9oz, and I shortened the buffer spring an inch. It still wont even cycle factory 115gr Remington. I'm thinking I need to just ditch the Adams Arms piston, and go DI with an adjustable gas block. Thoughts?

Well, good luck. I don't know if that will solve it, cheap to try though.

[gat0r]

that gas port sounds too big, but i havent kept up w/ 300blk.
that is significantly larger than everyone who posted success on drilling their ports.

what is velocity of load w/ 115s? 2000+

if those wont cycle w/ adj piston, i dont see the adj DI system working.
def. cheap to try it since you already have piston.

gas block & gas port lining up properly?


also the peeps who drilled their own ports @~.107-.110 -- are using H, H2 or H3 buffers

[GAP]

that gas port sounds too big, but i havent kept up w/ 300blk.
that is significantly larger than everyone who posted success on drilling their ports.

what is velocity of load w/ 115s? 2000+

if those wont cycle w/ adj piston, i dont see the adj DI system working.
def. cheap to try it since you already have piston.

gas block & gas port lining up properly?


also the peeps who drilled their own ports @~.107-.110 -- are using H, H2 or H3 buffers

I've seen similar success as you with people using a ~.110 gas port and standard buffer on full power loads. I can't explain my rifles problem, except maybe the piston system is designed for higher pressure cartridges.

The 115gr's are 2200fps.

Gas block and port are aligned, I can see a distinct carbon ring around the port.

[CJ]

It's the carbine length gas block location. There are many guys getting it to work with a pistol location, but even them it takes some tuning.

[GAP]

Just an update on my progress/stubbornness. Tomorrow i'm going out and giving it another try. I'm now up to an .171" gas port. Yes, ginormous! It will either work, or end of the barrel will simply fall off the gun. This is my last attempt with the piston, before I explore DI.