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Aberration79
17 June 2015, 19:47
Well I had so much fun building the last 2 rigs, and I bought 4 lowers. I managed to sell a dirt bike, so naturally I got replace one toy with another.

I have decided on an 8.5" 300BLK SBR that I will eventually get a can for. I got everything on a budget, except the stock.

8.5" 1:8 barrel from MAS Defense.
Spikes upper, only because its going on a Spikes lower. I had gotten 4 Spikes Zombie lowers. Zombies.
ALG 8" EMR Hanguards. Cheap and made by Geissele, can't be bad.
ALG QMS trigger, donated from my 16" I upgraded to an SSA-E
USGI BCG
MVB ARC Stock.
LPK will be from whats left over from the other builds I got lots of spares
I haven't decided on a muzzle device as I don't know what can I will get. I might just get a cheap birdcage for now.

I also got the Magpul BEV. My clamshell didnt work well for the ASA side charging upper and my designs of a barrel clamp were quite crude. But worked lol.

The only reason I didn't just get the whole thing from MAS is they wanted more for the Spikes upper, the BCG, and I don't like quad rails.

I don't know what optic I will use. I have had problems with red dots and astigmatism so I might get the Vortex 1x prism. Unless PA comes out with one.

I probably won't start building until the SBR gods bless me. But I might get anxious. :D Got to get the trust notarized and then file and wait.

tact
19 June 2015, 05:51
Here's a 300 I just finished.

BAD lower
2A Armament upper
KAC URX rail
9" Danger Close SS w/ 5R rifling
V7 gas block - pinned
MVB Arc PDW Stock
SCT Titanium BCG
Rainier slide lock CH
CMT straight bow trigger
B5 pistol grip
Mix of Battle Arms, norgon, and Seekins for LPK
Scalarworks mount and T2
Saker762

UWone77
19 June 2015, 21:51
Nothing wrong with building up a gun from all the left over parts you have from previous builds. Sounds like you have some decent parts in there.

The BEV Block is light years ahead of the clam shell. You'll be glad you made the switch.

Aberration79
27 June 2015, 20:07
So parts are coming in. Man. I can't wait to assemble it all. Going to have to split up parts for a while while the paperwork goes through. I was torn between the BEV and the Geissele rod. I am perfectly happy with the BEV. Already gone through and reset all my breaks lol.

I have already swapped the Spikes upper with the ASA side charger from the 16" I built. It won't fit a Seekins bolt catch, and I don't think a Phase 5 or any of the other trigger well bolt catches. Not sure what I will do, but I may end finding a friend with a welder and some skill.

I am VERY happy with the ALG EMR handguard. Very simple timing procedure, the material feels think enough to take a ding. Since I am waiting on paperwork and such I will just let this sit until I got the stamp. Then see we'll see what the final configuration is and get some pictures.

I figure if I just shove the parts in a corner I won't dwell on the wait. See ya at the necro haha.

Aberration79
27 June 2015, 20:11
Here's a 300 I just finished.

BAD lower
2A Armament upper
KAC URX rail
9" Danger Close SS w/ 5R rifling
V7 gas block - pinned
MVB Arc PDW Stock
SCT Titanium BCG
Rainier slide lock CH
CMT straight bow trigger
B5 pistol grip
Mix of Battle Arms, norgon, and Seekins for LPK
Scalarworks mount and T2
Saker762

You definitely went the higher $ route that I was really leaning too. Eventually though I got to counting pennies. :D I knew I was going to be adding accessories as it came together, and its going to add up.

Edit - Danger Close never came up in my search for barrels. Looking at it, I would have taken one of theirs had I known.

tact
29 June 2015, 16:33
You definitely went the higher $ route that I was really leaning too. Eventually though I got to counting pennies. :D I knew I was going to be adding accessories as it came together, and its going to add up.

Edit - Danger Close never came up in my search for barrels. Looking at it, I would have taken one of theirs had I known.

I had opted to build because I thought I could save some money. It didn't go that way. Once I had the option to pick individual items I got retarded.

Sak007
30 June 2015, 15:38
I have a half finished 300blk sbr due too the fact Wa decided to screw up my almost ready to be approved matching lower [bash]. So far this is what i have

8.5 Bison Armory Barrel
V7 TI Gas Block
V7 Extreme Environment Gas Tub
Silencerco Trifecta Brake
CMT Tac Left Hand Upper Receiver
Stag Nickel Teflon Left Hand BCG
AR Gas Vent
7in Seekins BAR Handguard borrowed from another rifle til my BCM KMR 7 comes .
Magpul MBUS
Vortex SPARC on a LaRue LT751.
Silencerco Saker 7.62

This is what will be ordered for my lower once Wa get's its shit together and my second form 1 goes from PENDING to APPROVED[:D]

CMT Tac UPH15 Ambi Lower
Hipertouch EDT
Bad Ass Ambi Saftey not sure which one yet
V7 TI Takedown Pins
V7 TI Mag Catch/ Release
V7 TI QD Endplate & Castle Nut
V7 Bolt Catch
V7 Buffer Tube
JP Silent Captured Buffer System
MFT Battlelink Minimalist
BCM Gunfighter Grip Mod 2

Sak007
30 June 2015, 15:50
This is my 300 upper sitting on my other registered SBR
http://i60.tinypic.com/zlo9k.jpg

Aberration79
30 June 2015, 18:01
A friend of mine just got back from a higher level class. I guess the 300 SBR is getting pretty popular. I was able to find 147gr plinking for 48c. That'll do if I can get it to cycle good.

Aberration79
30 June 2015, 18:04
I have a half finished 300blk sbr due too the fact Wa decided to screw up my almost ready to be approved matching lower [bash]. So far this is what i have

8.5 Bison Armory Barrel
V7 TI Gas Block
V7 Extreme Environment Gas Tub
Silencerco Trifecta Brake
CMT Tac Left Hand Upper Receiver
Stag Nickel Teflon Left Hand BCG
AR Gas Vent
7in Seekins BAR Handguard borrowed from another rifle til my BCM KMR 7 comes .
Magpul MBUS
Vortex SPARC on a LaRue LT751.
Silencerco Saker 7.62

This is what will be ordered for my lower once Wa get's its shit together and my second form 1 goes from PENDING to APPROVED[:D]

CMT Tac UPH15 Ambi Lower
Hipertouch EDT
Bad Ass Ambi Saftey not sure which one yet
V7 TI Takedown Pins
V7 TI Mag Catch/ Release
V7 TI QD Endplate & Castle Nut
V7 Bolt Catch
V7 Buffer Tube
JP Silent Captured Buffer System
MFT Battlelink Minimalist
BCM Gunfighter Grip Mod 2

I love the BAD stuff. I have their Ti EPS pins on my 16", the regular EPS pins on the wifes. I got another set of EPS coming for this build. I have the normal long and high levers and the cranks. The cranks work very well. For this I ordered 2 hybrids and I will mix and match. I think a crank on the thumb side, hybrid in the trigger finger. Maybe in a few years I will start replacing with the Ti stuff. Its such nice bling lol. I have the JP buffer in my 16" and I have had no problems, but it woundn't fit in this ARC tube.

I have a MOE K2 grip coming, Ergo handstop, some keymod panels. A Surefire comp and then a Phase 5 bolt catch to fit my ASA side charger.

Aberration79
19 July 2015, 19:08
So here she shits in her initial pistol configuration. I am very pleased so far.

http://i364.photobucket.com/albums/oo90/Aberration_01/031A471D-8247-49D2-BF6B-7A5C54ED1255_zps3ohrjdbt.jpg

I used a Magpul MOE-K2 grip. Very nice feeling. I liked the MIAD I put on the wifes 16" 5.56 build but the dang backstrap was a pain. So I got the MOE and am not disappointed. I love Magpul, my AK needs some love. What I don't like is I got 2 of the inserts to hold a bolt and firing pin, the though of spare parts on the rifle is very appealing. But the dang thing fell out with the bolt on the first round. :D
I used a Palmetto State Armory pistol buffer tube kit. Looks the same as my Carbine just large enough not to take the stock, good no questions about constructive possession if there ever was.
The KNS pins I will probably never need, but insurance for pennies.
I have the regular long BAD on the left and a Hybrid on the right. I had the cranks and longs on mine and the wifes 16" 5.56's, and then they came out with the hybrid. The hybrid is nice on the right as the lone was too much under the trigger finger. I will probably get another crank for the left side.
I got a Ergo handstop. I wanted something to keep my hand from over running the handguard and me becoming the next Youtube star blowing my hand off like some have done with the KSG. I never used a handstop before, might have to get more. It also was textured for 'barracades', and used 2 keymod bolts. Most used 1. Insurance lol.
The Knights belt hook I got while looking at the handstop. With a single point sling and the hook on the front of my belt this thing is nice and secure.
I have a Primary Arms Micro Dot. its worked great on my AK. With my astigmatism I am not shooting far though.
The American Defense modular riser I am not please with. It works, its American Defense sturdiness. But the 'absolute' rise is more like a 2/3 cowitness with the Magpul BUIS. At least its modular.
I also got a jig to drill the recess for the gas block set screws. I can't find the e-mail with who it was. I worked great. I would rather do this and stake them than mess with another taper pin.

So I got 3 different rounds.
110gr V-Max from Beck/Right to Bear Arms
147gr FMJ from MAST
208gr A-Max from Armscor
All new brass.

Here are the primers.

http://i364.photobucket.com/albums/oo90/Aberration_01/4D4DD478-216B-4DD1-9D91-024D065362A2_zpsen3vufiu.jpg

I am not an expert but all the primers are flat. And only the Gemtech brass from the 110gr seems like it might be a bit hot with the firing pins indentation kind of mushrooming. All rounds ejected OK, and all locked the BCG on the last round.

I had 2 failures, the first 208gr didn't make it up the ramp. And I had 1 147gr that didn't fully make it into battery and had a light strike. Both rounds fired when reloaded. I shot 2x30rnd mag of the 147, 1x30rnd Mag 110gr and 2x5rnd Mags, and then 1 30rnd mag of the 208gr. I am definitely pleased all ran OK. Of course once I get my Form 1 the buffer and spring will be different. But I think the indications of the primer show I got enough gas.

Aberration79
19 July 2015, 19:21
P.S. If you can use one of these AR pistols proficiently then more power to you. I found the thing completely impractical and just unreasonable to handle given another tool. I like that I have gotten to test most of the components, but this whole thing is stupid :D Unless I have a friend that is interested in testing it out she is probably going to take a nap in the safe until the Form 1 comes back.

UWone77
19 July 2015, 20:07
P.S. If you can use one of these AR pistols proficiently then more power to you. I found the thing completely impractical and just unreasonable to handle given another tool. I like that I have gotten to test most of the components, but this whole thing is stupid :D Unless I have a friend that is interested in testing it out she is probably going to take a nap in the safe until the Form 1 comes back.

What about shooting the pistol made you feel that you weren't proficient?

Aberration79
19 July 2015, 20:44
There was just no comfortable way to shoot it. I could get rounds on target no problem, the first one. The recoil was too much without a stock for any type of follow ups. And then of course I could get up on it and get a nice cheek weld like it was a rifle, but then I had a buffer tube poking my collar bone.

Dstrbdmedic167
19 July 2015, 21:00
There was just no comfortable way to shoot it. I could get rounds on target no problem, the first one. The recoil was too much without a stock for any type of follow ups. And then of course I could get up on it and get a nice cheek weld like it was a rifle, but then I had a buffer tube poking my collar bone.

I know you're SBR'ing but a Thorsden buffer tube kit or KAK Shockwave would help... I've had no issues with my 12.5" pistol using the Shockwave and can Cheekweld it comfortably and really get on target comfortably..

Edit: Those Gemtech are definitely warm in your pistol.. I'd keep a watchful eye.. youre not too far fron flat primers and swipes...

UWone77
19 July 2015, 21:07
There was just no comfortable way to shoot it. I could get rounds on target no problem, the first one. The recoil was too much without a stock for any type of follow ups. And then of course I could get up on it and get a nice cheek weld like it was a rifle, but then I had a buffer tube poking my collar bone.

I know what you mean, when I shot my AR pistol regularly, it was pre-KAK Shockwave and Sig Brace.

I think the best shooting style for my personal tastes when shooting an AR pistol is a single point sling and SAS style.

Aberration79
19 July 2015, 22:52
I know you're SBR'ing but a Thorsden buffer tube kit or KAK Shockwave would help... I've had no issues with my 12.5" pistol using the Shockwave and can Cheekweld it comfortably and really get on target comfortably..

Edit: Those Gemtech are definitely warm in your pistol.. I'd keep a watchful eye.. youre not too far fron flat primers and swipes...

I have dabbled in reloading and read the manuals. I have never worked a load up that hot. But that was my first thought with them.

Aberration79
19 July 2015, 22:54
I know what you mean, when I shot my AR pistol regularly, it was pre-KAK Shockwave and Sig Brace.

I think the best shooting style for my personal tastes when shooting an AR pistol is a single point sling and SAS style.

Forgot the sling on the chair. I got enough ammo and a few people quite interested in the build so I am going to have to give it a try. I guess just pushing out instead of pulling in. And try not to look too tacticool doing it lol. God the laws are so stupid.

UWone77
20 July 2015, 19:10
Forgot the sling on the chair. I got enough ammo and a few people quite interested in the build so I am going to have to give it a try. I guess just pushing out instead of pulling in. And try not to look too tacticool doing it lol. God the laws are so stupid.

It's not perfect, and it can get tiring shooting like that, but AR pistols in general are a compromise and only exist because of NFA.

Soisauss
20 July 2015, 21:31
It's not perfect, and it can get tiring shooting like that, but AR pistols in general are a compromise and only exist because of NFA.

Only reason I built one and currently treading the NFA waters with the new sub combat pistols ( Anggstadt Arms UDP-9) in mind to build.

Jerry R
22 July 2015, 12:02
So here she sits in her initial pistol configuration. I am very pleased so far.

http://i364.photobucket.com/albums/oo90/Aberration_01/031A471D-8247-49D2-BF6B-7A5C54ED1255_zps3ohrjdbt.jpg

Looking at the build (very nice!) I am curious as to which suppressor you are considering with that barrel length and handguard.

And I definitely agree with Dstrbd -- cratering is a sure sign pressure is up. Unless that load is extremely accurate, you may want to consider dropping the load slightly.

Aberration79
24 July 2015, 09:34
Thanks! I am going with Surefire once I get around to it.

All of those loads are 'factory' loads with new brass. I didn't have the time to make some or find some and load them. I have heard nightmares about getting the light and heavies both to cycle, I didn't want to throw reloading into that.

So I need to test out the PDW stock that I have on my 16" 5.56. Buddy has a chrono so I am going to bring it out and get the measurements from some 5.56. And then I will chrono some of this 300.

Aberration79
10 January 2016, 18:30
Well my darn stamp finally got approved. Went through the work and got the MVB stock installed and all that. It ended up short stroking frequently on the 147gr FMJ's. So I had to order the Carbine buffer. Though I wondered about getting at the weights and removing some. But now if I run a rifle length upper I got a buffer for the hell of it. I also went with a Surefire 3 prong muzzle adapter as a friend had a Surefire suppressor.

Just today I ran my friends Surefire finally. Running 208gr subs from Armscore. Ran a mag, perfect function. Zero'd at 50 previously with 147gr FMJ, with Magpul BUIS. Was able to hit my buddies man size targets at about 75yds without any adjustments. Didn't do much thorough testing. The clearance to the handguard is about 1/8th inch. But it fits lol. It was a cheaper barrel so I am eyeing replacing it anyways. I'd like maybe 1/4-1/2in more. I love how light this thing is and the ergonomics of it all.

It probably shoots way better than I do. I got the Primary Arms 1-6x 300BLK. I also recently picked up a target stand and a 8" and a couple 4" round plates to shoot at.

All in all I couldn't be happier. Kind of pondering getting some cerakote. We'll see how long it last until something breaks :D

BoilerUp
10 January 2016, 18:50
It's not perfect, and it can get tiring shooting like that, but AR pistols in general are a compromise and only exist because of NFA.

...and state laws that don't allow for loaded rifles in or on vehciles, such as in WA.

Dstrbdmedic167
10 January 2016, 19:06
Pics or it didn't happen...

Glad to hear you got it straight and it's running well for you.

Aberration79
10 January 2016, 22:40
http://i364.photobucket.com/albums/oo90/Aberration_01/E3E192AA-6E08-4CA4-876E-555EA55005DD_zpspi0rpfpg.jpg

Joelski
11 January 2016, 04:27
I know you're SBR'ing but a Thorsden buffer tube kit or KAK Shockwave would help... I've had no issues with my 12.5" pistol using the Shockwave and can Cheekweld it comfortably and really get on target comfortably..

Edit: Those Gemtech are definitely warm in your pistol.. I'd keep a watchful eye.. youre not too far fron flat primers and swipes...

I'm with the OP on shooting. Never interested me to fire it in pistol mode, nor any other AR pistol config; I guess I just have a rifle image thing going on when it comes to AR's.

Flat primers and swipes: 'splain, please. Never heard these terms before. To my knowledge, the 300 is one of the least finicky calibers with respect to gas volume and pressure.

Jerry R
11 January 2016, 07:39
Flat primers and swipes: 'splain, please.

I believe "swipe" is defined as:
Primer swipe is caused by the ejector starting to push the case off the breech before the firing pin has fully retracted.

Flat primers would normally be defined as "showing signs of pressure" - that would be pressure higher than normal, something to watch.

If you look at an unfired cartridge, the primer cup has rounded edges.

If you look at a fired case that is "normal" the primer strike is clean and shaped like the firing pin tip. The edges of the primer cup are still visibly round.

A swipe would show a little drag mark of metal at the edge of the firing pin indentation (wish I had a picture for you) - in other words, not a "perfect" indentation.

A flat primer would be where the edges of the primer cup are no longer round - the edge has "flowed" under pressure to square up with the edges of the primer pocket on the case. This may, or may not, be a bad thing depending on the amount of pressure being generated. I generally back off my powder charge if I start to see flattening on the primers.

Another term you may hear is "smudge" or something similar. It would be a smoky stain around the edges of the primer pocket. This is either a really loose primer (not likely) or high pressure. The seal between the primer and primer pocket has been compromised, and flame is leaking back through the primer pocket - definitely not a good thing.

Lastly, "cratering" --- this is where the firing pin indentation looks like a miniature meteor strike - the outer diameter of the indentation has a ring around it where the metal has flowed under heat/pressure.

Most reloaders consider any (or all) of the terms as being indicative of increased pressure - or, if a known "safe" load is being used, some might indicate a potential case failure.

Again, if other definitions are more accurate, please speak up. Hope this helps.

Dstrbdmedic167
11 January 2016, 07:45
Jerry answered better that I could have. I was waiting to get to a PC before I responded. Thanks Jerry

Slippers
11 January 2016, 09:14
Swipe usually pertains to marks on the rim of the case due to the ejector cutout on the bolt face, such as this:

http://www.pirate4x4.com/forum/attachments/outdoor-sports-recreation/673508d1337743127-case-head-swipe-2012-05-21-17.35.22.jpg

With an overpressure load, the brass flows into the ejector cutout slightly, and then the bolt face rotates, and leaves the swipe mark.

Jerry R
11 January 2016, 10:00
Thanks Will. I wasn't positive on the swipes. My search Kung-foo found a lot of references to firing pin swipes, so I went to "The High Road" dot com and used their definition instead. Usually have reasonably accurate info there. Appreciate the correction.

Joelski
11 January 2016, 10:28
Thanks, fellas. Those are both good things to know!

Slippers
11 January 2016, 12:15
Thanks Will. I wasn't positive on the swipes. My search Kung-foo found a lot of references to firing pin swipes, so I went to "The High Road" dot com and used their definition instead. Usually have reasonably accurate info there. Appreciate the correction.

I believe primer swipes are more common in pistols? I have never seen them on an AR is all.

Or might be one of those things where a primer swipe on a pistol is the same as a pierced primer on an AR? Different terminology for the same thing...

Aberration79
20 May 2016, 11:58
Well crap. I decided to go with a Dead Air Sandman-S. So I swap out the muzzle device and.... I don't think its going to clear. I also upgraded the front sight to the MBUS Pro and the Blitzkrieg tritium spike. As you can see the spike is offset to accommodate the tritium vial. But I think they offset it the wrong direction. I don't think it will matter much, except I lose a tad of sight radius, I am going to flip it how the sight comes up. That way the post has more protection.

http://i364.photobucket.com/albums/oo90/Aberration_01/7AF52EF8-092A-4E2E-AB3E-844F1143DA0B_zpsvmeafoe6.jpg

So because the can isn't going to clear the handguard, I am patiently waiting for a KAK 9" 1:7 stainless barrel.

Aberration79
20 May 2016, 13:33
Fuck it. I am going to swap out the American Spirit Arms side charging upper for a traditional upper with BCM charging handle. I like the function. I don't really like needing a custom carrier. I don't like how quickly the inside load bearing surface wore at. And I don't like their customer service. As for function. Well the PDW buffer needs to be held back to open the receivers. So I would pull the bolt back and stop with the bolt catch, hold the buffer catch, then release the bolt. Its just barely not enough force to close the bolt. The ASA upper doesn't have a bolt assist, and its non-reciprocating, the charging handle is not attached to the carrier. So I have to use my finger to push the bolt closed through the ejection port. Not an ideal situation. Now I will have a forward assist to close the bolt.

Come on USPS.... I already got everything broken down. Need that barrel to clean it up.

Aberration79
20 May 2016, 14:31
Just the additional length I needed. Now this barrel worked with 110gr, to 220 subsonic. All cycled properly. Hopefully this new barrel doesn't change that. The half inch shouldn't add to much more, but its some. But the gas port is obviously larger. I have a heaver puffer for the ARC in case I need it. And then when the Sandman-S gets out of jail, lol. Trying to chase the unicorn of 110-220gr bullets working suppressed and unsuppressed. I'll get an adjustable gasblock if I have to, but I would rather not.

http://i364.photobucket.com/albums/oo90/Aberration_01/Mobile%20Uploads/A61E179D-DA99-49E1-A9C1-81DF0C0B0ABF_zpsfbogv5xs.jpg

wsaraceni
31 May 2016, 03:22
Now you have a spare barrel and upper. Time for SBR another lower. That's the rules.

UWone77
31 May 2016, 23:31
Now you have a spare barrel and upper. Time for SBR another lower. That's the rules.

Ha.... I'm sure people have started builds with much less than just an extra barrel. [:D]

Aberration, I agree... anything that uses a proprietary BCG is generally a no-go in my book.

Joelski
1 June 2016, 14:34
My 300 is my absolute, funnest gun I've ever owned, period. It's a blast!

http://i997.photobucket.com/albums/af93/Joelski144/ARs%20and%20Pistols/MK%2018/20160503_213819_1.jpg~original

SINNER
1 June 2016, 15:22
Ha.... I'm sure people have started builds with much less than just an extra barrel. [:D]

Aberration, I agree... anything that uses a proprietary BCG is generally a no-go in my book.

I was sent a 7.62x39 bolt by mistake once and it grew into a rifle. Lol

wsaraceni
1 June 2016, 16:02
Ha.... I'm sure people have started builds with much less than just an extra barrel. [:D]

Aberration, I agree... anything that uses a proprietary BCG is generally a no-go in my book.

Including KAC? :)

Aberration79
3 June 2016, 21:37
Now you have a spare barrel and upper. Time for SBR another lower. That's the rules.

I have 2 stripped lowers. Problem is, my next SBR I wanted to be like a San Tan or something. What I do got is a lot of parts I should put up for sale to pay for a San Tan lower to SBR LOL.

Edit - So I explain to the wife I have a lot of bad influences on the internet. She agreed. I told her I should get some parts together to sell to help fund another build. She said thats a great idea. Maybe she didn't catch the part about "helping to fund". Whatever. Its all the approval I need. Just beg forgiveness later. Must have been a misunderstanding.

Aberration79
3 June 2016, 21:41
I have to say, the side charging was really sweet. Clearing and charging was just so much easier. I have seen this design, which is almost good. At least it only uses a custom Cam Pin. And a spare cam pin is easy to keep on hand.

https://gibbzarms.com/product/g4-side-charging-upper-receiver/

Not sure about this one, not enough info or at least a bit ambiguous. It says no modifications.

https://rouschsports.com/shop/ar15-upper-parts/side-charging-non-reciprocating-upper-receiver-newest-and-best-available/

Aberration79
3 June 2016, 21:46
Damn it. That Gibbs looks real nice. Now I am wondering what kind of lower I could match it too.

See if I got a fancy SBR lower to make the 300BLK from, then I could use the standard lower to make a short 5.56 from.

I hate working over time. And there are these things my wife keeps nagging about, you guys heard of them? Bills? All I know is I look at the bank account and see plenty of $ and I don't know why I can't spend it LOL.

Aberration79
3 June 2016, 21:49
Including KAC? :)

For me its the custom parts. I really doubt a BCG will go down. But what if? Then what do I replace it with? SOL. I really hate not having spare parts. Even though I always forget them and of course a gun goes down at the range and the freaking spare is at home.

When Sandy Hook happened I decided to get on it and build. Took a year for the lowers to get in stock. I bought enough to build 2 including spare springs, detents, firing pins. That and getting the Magpul BEV block were the best calls I made in my builds.