First AR-15 / build need advice

[hdrolling]

I have the 16" non-fluted mid but with a 15" hand guard in keymod, I used a BCM BCG and added a BCM LPK to a stripped BCM lower. Using a Geissele SSA, BCM 44 AMBI charging handle and the CTR.

Great rifle, but doesn't perform or shoot any better or worse than my Daniels defense or Noveske. I was using BCM on all my new build until I saw the sionics that I picked up for $99, their going to be my new go to BCG.

Any reason for the 13" over the 15"?

bcm 2 by hd_rolling, on Flickr
bcm 1 by hd_rolling, on Flickr

[Desert Trekker]

I would ask the same question as titsonritz: "Any special reason for the KeyMod?".

I have BCM uppers in both KeyMod and MLOK, and of the two I prefer the MLOK as the attached accessories seem to lock-up more securely. You may want to look at this comparison: Modular Rail System Comparison Abstract #19427 Presented By: Caleb McGee Date: 4 May 2017 KeyMod TM vs. M-LOK TM https://ndiastorage.blob.core.usgovc...McGee19427.pdf

Neither of these two models lock-up attached accessories as securely as the old MIL-STD-1913. Since you are seeking opinions on three BCM KeyMod products, if you are interested in the MIL-STD-1913 it is manufactured by Bravo Company: BCMGUNFIGHTER™ QRF (Picatinny) Handguard https://www.bravocompanyusa.com/BCM-...uard-s/228.htm I still use the the "old" Picatinny hand guards and like them a lot; no complaints about width or weight.

Regarding the buffer, I have always gone with the "Default H Buffer".

Regarding the BCM® Bolt Carrier Group, I have and always will include it with the purchase of an upper.

Regarding the stock, BCM and MAGPUL make very good stocks. I prefer the B5 SYSTEMS ENHANCED SOPMOD STOCK, and also use several BCM Stock Mod 0.

[kiwdahc]

Looks like I will be looking into the uppers with the MLOK system as there was no reason for the keymod other then I thought it was the best from reading around but it appears otherwise.

Are the 15” rails superior to the 13” or 12” ones? I figured the shorter rail would weigh less which would be a benefit but other then that am not sure.

[Desert Trekker]

kiwdahc,

"best" is very often subjective in our choices (reference your most recent KeyMod note). In response to your hand guard length question, the weight difference shortest to longest is negligible. If you use the longest, your options for mounting accessories is greater and you have more area to utilize for a supported shot. I find a fifteen inch hand guard is great to place a SUREFIRE X300U-B http://www.surefire.com/illumination...aponlight.html at 12 o'clock just behind the muzzle device and a fixed BUIS nearly touching the light if a red dot optic is mounted (I have a long reach). This particular light has a control switch on each side, so switching shoulder position has no effect on operating the light equally well. Many guys prefer a short or medium rail; I use these also. I recommend only that the weight difference between HG lengths is not your determining factor.

[voiceofreason]

kiwdahc,

"best" is very often subjective in our choices (reference your most recent KeyMod note). In response to your hand guard length question, the weight difference shortest to longest is negligible. If you use the longest, your options for mounting accessories is greater and you have more area to utilize for a supported shot. I find a fifteen inch hand guard is great to place a SUREFIRE X300U-B http://www.surefire.com/illumination...aponlight.html at 12 o'clock just behind the muzzle device and a fixed BUIS nearly touching the light if a red dot optic is mounted (I have a long reach). This particular light has a control switch on each side, so switching shoulder position has no effect on operating the light equally well. Many guys prefer a short or medium rail; I use these also. I recommend only that the weight difference between HG lengths is not your determining factor.

Basically... how long are your arms? Will you ever need/reach the end of a 15" handguard using your style of shooting?

[hdrolling]

Looks like I will be looking into the uppers with the MLOK system as there was no reason for the keymod other then I thought it was the best from reading around but it appears otherwise.

Are the 15” rails superior to the 13” or 12” ones? I figured the shorter rail would weigh less which would be a benefit but other then that am not sure.

I like the longer rail since I shoot mostly supported at the range, less chance that My barrel might touch the bag or support, but it really is just your preference. I just noticed all your choices were 13".

The length and and mounting system is all based on what you "want", I own keymod , Mloc and quad mounts like my keymod better. I have 10", 13", three 15" and a 16.7" rails, I like the 15" for my style of shooting.

Since this sounds like it will be a little higher cost build it's best to be sure what you want, maybe head to a local gun store and get a feel for the the different lengths?

[SiGfever]

Take a good look at this upper. I really like my BCM 14.5" ELW w/13" KMR, but if I had of known about these guys, I would have bought this...

http://sionicsweaponsystems.com/stor...hree-e-ur.html