Some of you guys have seen me browsing around picking for info lately.  Well here is why.  The Twins are not identical but conceived at the same time. As for #1 I've been wanting a 300BLK SBR/suppressed for a long time. So while I wait for my papers (Form 1 for the SBR and Form 4 for AAC 762-SDN-6) I built a pistol.  Well, I couldn't make up my mind what I wanted for it exactly so I had left over parts that were purchased and not used.  What do we do with left over parts?  Sell them or use them.  I used them (not all though, some will be on EE).  Now I have a 10.5" 5.56 upper that is just begging for it's own lower.  Hence #2 comes along.  Bought a Spikes Punisher lower for that one and now the Wife says "Hey, I want one".  Well that is where #3 comes into play but I am waiting for an Aero Precision "pew pew pew" edition lower to arrive at my FFL for hers.  She saw it and JUST HAD to have it.  Nonetheless, let me introduce the hive to our first 2 born pistols.  Once the 300BLK papers come back the other 2 will stay as pistols.  Enjoy.  *Warning... I am not Stickman when it comes to photos.  Just enough for you guys to know that there is another brother out there building shit and getting it done.  Wish I could do better.  

One thing I would like to mention is that I know optics are a touchy subject and I probably could have done things differently with the Eotech.  But my father is a retired LEO with Stage 4 cancer.  He had a broken Eotech on one of is old duty rifles and handed it to me with the expectation that I could do something with it so I called Eotech and asked them what to do.  I told them my father's situation and that he was issued this sight and that I personally didn't pay for it.  But could I send it in for repair? They said "send it to us".  Well turns out it was an older model they no longer make.  While I was overseas (I travel for work) my wife gets a package in the mail and it's this EXPS-2.  I was blown away.  So I am using this sight for now.  A "special" build for my old man will be in the works soon using this sight. But for now it rests on this setup. (that's a separate thread and build all together)

300BLK 8.5"

Rainier Arms select barrel
CMT billet upper and lower
CMMG LPK
Rainier Arms UPK
Rainer Arms phosphate BCG
Rainier Arms Raptor charging handle
Fortis gas block
AAC Brakeout V2
Fortis Rev 7 rail
Sig brace
KAK super tube with spacers
ODIN mag release extension ( I have small hands)
Magpul MOE+ grip (bought this BEFORE I realized there was the K2)
Elzetta light with tape switch (this thing is BRIGHT!!)
EOTECH EXPS-2
Diamond Head Inlay BUS (they don't lay flat but it doesn't bother me. Others with OCD it might)





10.5" 5.56 NATO

Aero Precision 10.5" barrel (GVT profile)
Aero Precision BCG
Rainier Arms upper (seeing a pattern here fellas?)
Spikes Punisher Lower
CMMG LPK
Fortis gas block
Rainier Arms UPK
Sig brace
Phase 5 HEX-2 buffer tube (I prefer this over the KAK)
Magpul MOE+ (had it as a spare)
BCM 9" KMR
AAC blackout flash hider
Noveske charging handle
Haven't decided on optics yet





The dealer holding my can let me test fit it to my 300BLK.  



I know there are things I am forgetting.  Just ask and I'll let you know.  I've very proud of these rigs and very happy to have had the help and support from the hive here with building them.  I haven't "touched them off" yet but I plan to soon.  All torque specs are solid and head spaces are good.  Everything was gone through with a fine tooth comb.  Both rigs are running a standard carbine buffer and spring.  I have heavy ones just in case.  Should be a good ride on test day at the range.  I'll post updates as they come along.

Yes I have the KAK super tube AND the Phase 5 HEX 2.  I prefer the HEX 2 for fit, feel and eyes.  But that is just my opinion.  Maybe with a little encouragement I can do a review on both and post the results here.


Stay tuned......

Love that .300
The Fortis rail looks great with the CMT upper. I've been debating on a new upper and rail pairing and that was one combo I was looking at.

I really like it so far.  Plus it uses the stock barrel nut which I am a fan of. It's really versatile and lightweight.  The price ain't bad either.  All in all I think the Fortis Rev is a good package for anyone looking to utilize a lot of rail space.  I almost put one on the 10.5" but I really heard good things about the KMR so I chose to try it out.  

I think you'll be happy with the Fortis.

Well I figured I would offer up a range report now that I finally got to touch off a few rounds from both pistols.  No report on groups or accuracy, just reliability.  

8.5" 300BLK all un-suppressed:

Started with 125gr super sonic:
Had 2 FTE in the first 2 magazines (Magpul Johnny PMAGS not fully loaded, about 10 rounds each).  I knew that BCG did NOT have an oring on the extractor. So I changed it with one that did and changed the standard buffer for an H buffer.  Then cycled 30 rounds with no issues so I put the previous non-oring extractor BCG and standard buffer back in and it ran like a sewing machine the rest of the of 125gr.  No issues.  140 rounds total.  

Then came the 208 sub.
100 rounds.  No issues.  None.  Perfect.  With the non oring BCG.  Also ran standard and H buffer.  Both ran fine.  

10.5" 5.56

300 rounds of XM193
No issues.  Standard buffer, H buffer, oring BCG and non-oring BCG.  Ran like a top.

All in all I'm happy.  Only thing I am concerned about is that the 10.5" 5.56 was throwing brass at about 1-2 o'clock.  The 8.5" 300BLK was throwing brass at 4-5 o'clock on both grains of ammo.  I think the 300BLK is dialed where I need it but I am not sure about the 5.56.  Is that OK to throw brass that far forward or does that mean I need to slow it down with a heavier buffer?  It did seem to come back about 2-3 o'clock "sometimes" when I put the heavier buffer in but not a whole lot.  i wasn't too concerned as it was running well.  Suggestions???

Thanks for the input guys.


ETA:  Oh!!  Almost forgot.  The Phase 5 HEX2 buffer tube felt the best out of both.  I'll be changing out the KAK on the 300BLK for a Phase 5 this week.  It just felt right to me.  This is just "MY" opinion.  The brace on the KAK rotated a little but not much.  Nothing to be too concerned about but I just liked the LOP better on the Phase 5 and it "went to my cheek" better and faster than the KAK.  Again, just my opinion and exp.  Hope this helps anyone looking to decide.

Nice report on a couple of really nice heaters!

- OS

Curious to hear the brass thing. Mine does the same at 4-5' out.
 

As far as the ejection pattern, can be used as part of evidence to diagnose a prob, but shouldn't necessarily be considered indicative of one, if gun runs well.

While overgassed ARs do tend to eject before 3:00, that's not absolute proof, there are other variables. Heavier buffer or spring is a tuning "kludge" to get a slower, less violent movement of BCG, which generally will change ejection angle some too.

As you probably know, the best way to really tune one is with adjustable gas block, and I assume that Fortis on the 5.56 one isn't.

But then all in all, if rifle runs 100% on every type ammo you want to put through it, "if it ain't broke don't fix it" may best apply.

- OS

Very true.  And I wouldn't consider them to be 100% just yet.  It was only the first day.  But it was a good one.  Maybe after a thousand rounds or so I'll be confident that I am GTG.  You are correct, the gas block is NOT adjustable and I have no intentions on changing it at this time.  But if ultimately I need to then I will.  However, I am going to install an adjustable gas block on my Wife's 7.5" that I am building just for data mining.  Your input is excellent and helps a lot.  Thank you.

Aero suggests using an H-Buffer with their 10.5" barrels though they said it will work well with a std buffer too.  I would lean to the H-Buffer for the nudge and since X193 is fairly hot it should be expected to go a bit forward.  Run another 100 rounds of it and then try some cheaper ammo like some commie steel and see how it throws.  For me I like brass, but I also strive to be able to run any type of ammo through it and so far my Aero 10.5" has shot perfectly with both std and H buffers with no hick-ups with any ammo.

Congrats on two very nice builds.

I like the Fortis rail on the BLK. I wanted to go 8.5" over my 10.5" but I will have an 8.2" soon, not in BLK but that's besides the point. Now in pistols I have 2 10.5"'s.

Enjoy!