Need buffer/stock help


Ok, so as I said when I came here, I am new to guns and decided to build myself an AR15. Well, I approached it like a girl and wrote down everything I thought was pretty and would want on my rifle. I did do some research too though. Anyway, I am ordering one component at a time, each paycheck. It’s time for me to order my stock and the one I chose was Strike Industries Viper PDW stock. What I like about it was it seemed minimalist (which I like), it also looked comfortable. It’s pretty short when collapsed, and just pops open at the push of a button. But then I read about LOP. It’s no wonder most rifles seemed awkward when I fired them, it’s because they are too big for me. So I learned to measure for my LOP, which is just under 11-1/2". Extended this stock gives me 11" which I am happy with. Here’s the problem. I think maybe it won’t work for what I want to build. I have an 18" barrel (.223 Wylde) with rifle length gas system. I know this stock and buffer are not intended for rifle length, or at least, I assume it’s not. So question. Can I use this on my build? If not, does anyone have any suggestions for an adjustable stock that would fit me? I did like this stock because if not extended, it was pretty short when collapsed and that also appealed to me. Suggestions. Be gentle. Still learning. Thanks in advance.


As long as you have the proper spring and buffer
It doesn’t matter how long the barrel is as far as the gun functioning. 18" barrel is not a problem. That’s only 2" more barrel than an M4. I have run a 24" heavy barrel varmint upper on a collapsible stock lower with no problems. 223/5.56 doesn’t cause the kind of problems that 308/7.62 seem to cause.


Correct! Just don’t put a rifle stock spring and buffer in an adjustable receiver Extention (Fancy Tech term for Buffer Tube).
My go to AR15 is an 18” rifle length DMR with an adjustable stock.


So it comes with its own buffer assembly/spring, but is supposed to be compatible with any standard bcg. so it’s the buffer that it came with and spring that was concerning me. I just want to make sure it will work.


Should be just fine. You ordered quality parts not something off of ebay.


No. nothing off ebay. Thank you @AgentVenom and @shooterrex


@RedAngel Let us know how the build goes or if you have more questions. I’m a Colt AR15, M4, M16 certified armorer. I’m sure there are some real gunsmiths on here too.

Always willing to help.


Standard buffer systems for the AR are either ‘rifle’ or ‘carbine’. The tubes, springs, and buffers are different lengths between those two systems, so parts should not be mixed between them (do not use a rifle buffer in a carbine buffer tube, for example). Adjustable stocks usually use a carbine buffer system.

In most cases, the barrel and gas system will work just fine with either of the standard buffer systems (a 20" barrel with a rifle length gas system will work with a carbine buffer system). In general, problems with having to match the buffer system to the AR you are building, is something you tend to encounter when moving farther away from a standard AR (odd calibers, short pistol builds, etc).