Modern Sporter builds Q&A

[BCreserveMP]

So go with standard Mil-Spec stuff unless you want to mod the strike force industries one

I have a Radian FA waiting for my build. By eyeballing it next to a milspec FA it looks identical. I'll report back on fit/function once my MS is assembled.

[anoxia]

So go with standard Mil-Spec stuff unless you want to mod the strike force industries one

Some people bought the Strike Industries FA in advance of getting their receivers so instead of tossing them aside you can mod them so that you can still use them. Why? SI is one of the readily available companies who have colour options for their upper and lower parts. So people who are trying to customize their gun with a certain colour would like to make the SI FA work if possible.

[jiffx2781]

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[Bigrounds8mil]

Is the MS picky with handguards or will just about any work?
Not sure about the machining dimensions on upper receiver but looking at an Aero Precision atlas R1

[griffin86]

Is the MS picky with handguards or will just about any work?
Not sure about the machining dimensions on upper receiver but looking at an Aero Precision atlas R1

My Aero handguard wouldn’t fit.

[Unexpected]

Some people bought the Strike Industries FA in advance of getting their receivers so instead of tossing them aside you can mod them so that you can still use them. Why? SI is one of the readily available companies who have colour options for their upper and lower parts. So people who are trying to customize their gun with a certain colour would like to make the SI FA work if possible.

Ok I didn’t know that about the strike industries fa, I’m new to the world of Ar type rifles. Thanks for the info

[cr5]

I have a Radian FA waiting for my build. By eyeballing it next to a milspec FA it looks identical. I'll report back on fit/function once my MS is assembled.

I put a titanium Radian FA in my upper, works perfectly. You should have no issues.

[AMET]

Is the MS picky with handguards or will just about any work?
Not sure about the machining dimensions on upper receiver but looking at an Aero Precision atlas R1

BCM KMR fit beautifully. No modification required.

[TysonA]

Does anyone know if the .936” superlative arms adjustable clamp on gas block will work with the MRA V1 handguard

[rimlick]

Strike Industries Strike Forward Assist Update - Working

Jiffx2781, I did the same thing. I bought a couple of Strike FAs for my current builds. When I installed them I had the same results, they ratchet the BCG forward but won't release it rearward. I compared a spare milspec FA to the Strike FA as I thought it might be a difference in either the pawl or plunger. The plungers were almost identical in length but there were subtle differences in the pawl design and outer spring lengths. Since the FA was catching, I thought the cause was either the pawl itself, the pawl range of rotation or the strength of the outer spring (milspec spring was shorter). So on a lark, I took apart a milpsec FA and replaced the pawl and outer spring on the Strike FA. Low and behold it worked (BTW the Pawl Detent and the Pawl Helical Compression Spring are not interchangeable). I tried three different BCGs on both of my modified Strike FA MS uppers and they seem to work. For reference, I tried swapping the outer spring only but had mixed results as it caught my JP SPCS when I was removing the upper receiver and wouldn't let go.

Working. Replaced the Strike pawl (2) and outer spring (not shown) with milspec parts.

Reference. Image linked to AR15.com parts diagrams

(1) Forward Assist Pawl Retaining Pin
(2) Forward Assist Pawl
(3) Forward Assist Pawl Detent
(4) Forward Assist Pawl Helical Compression Spring
(5) Forward Assist Plunger

Great post. I know it's asking a lot but do you have any pictures of how they differ?;,z