So over winter im looking into doing a qcb build 10.5 inch in 300 blackout. Now im curious should i just buy an upper and lower and barrel separate or should i buy a compelte upper and build from there? Also if i do get a barrel what twist rate should i looking at ive seen 1:8.5 and 1 :7 not a huge diffrence but im not sure what the diffrence on paper would be.
First ar15 build qcb
- Thread starter 1rstEncountr
- Start date
If you are mechanically inclined, confident in your ability and have patience do a complete build with individual parts. You will have a ton of gratification once the rifle is dialed in and cycling to your satisfaction, however be warned home builds "can" be frustrating in the beginning. Occasionally home builds will not retain their value compared to ready builds when it's time to sell. There are pros and cons.
Depending on projectile weights 30 Calibers (300 ACC) perform better with 1/10>twist rates and 5.56 (223 rem )with a 1/7> twist.
I prefer home builds over ready builds and in the process of assembling another. Just received a 20" AR Bob Jury Custom Barrel for long range shooting.
Depending on projectile weights 30 Calibers (300 ACC) perform better with 1/10>twist rates and 5.56 (223 rem )with a 1/7> twist.
I prefer home builds over ready builds and in the process of assembling another. Just received a 20" AR Bob Jury Custom Barrel for long range shooting.
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There is a plethora of parts and opinions on the AR rifle that can make ones head spin. This is a manufactures short list of fine quality parts,
Aero Precision and Spikes Tactical forged upper and lower receivers.
Magpul or IMI for the pistol grip, buttstock furniture and magazines.
Troy, ATI and Houge for the forend.
Geissele fire control group.
CMMG or DPMS for the bolt carrier group.
BCM and DPMS for barrels, Charge handles and commercial buffer tubes kits.
Vortex opticals.
This is just a tip of the iceberg, however This will get you a fine AR until it's time to expand.
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Here's my home built 300BLK upper. Runs like a champ.
- Rainier Arms upper
- Daniel Defense MK18 RIS II rail
- Daniel Defense 10.3" 300BLK 1:8 barrel
- Troy Industries low profile gas block
- Spikes Tactical Melonite gas tube
- Daniel Defense BCG
- Griffin Armament M4SD comp
Lower is running a JP Tuned buffer spring and Spike's ST-T2 buffer
- Rainier Arms upper
- Daniel Defense MK18 RIS II rail
- Daniel Defense 10.3" 300BLK 1:8 barrel
- Troy Industries low profile gas block
- Spikes Tactical Melonite gas tube
- Daniel Defense BCG
- Griffin Armament M4SD comp
Lower is running a JP Tuned buffer spring and Spike's ST-T2 buffer
playinghooky
CGN Regular
- Location
- Lower Mainland
Those are rail covers probably made by Magpul?
View attachment 34526
Here's my build.
Daniel Defense upper, I have swapped out the NEA upper in favor of a DD upper since the pic was taken.
Custom 12 inch stainless barrel with pistol length gas system compliments of Suputin
Fail Zero nickel boron coated FA BCG
Standard carbine buffer and spring
Troy Alpha forend
If memory serves it has an 8 twist barrel. Shoots great and is very accurate.
Unlike 223 builds the 300BLK is nice in that it usually doesn't need a heavier buffer or anything special.
Keep in mind though that not all factory ammo will cycle in all rifles, it doesn't indicate a problem with the rifle if it won't. I had a PWS 9.75 inch 300BLK that wouldn't cycle Hornady 208gr factory loads but it would cycle my 208gr handloads without issues, powder choice is very important with this cartridge.
Hopefully you are a handloader and again remember that just because there is load data in your book that doesn't mean your rifle with cycle it. I've tried loads that work great in my bolt action 300BLK but won't cycle my semi's.
Here's my build.
Daniel Defense upper, I have swapped out the NEA upper in favor of a DD upper since the pic was taken.
Custom 12 inch stainless barrel with pistol length gas system compliments of Suputin
Fail Zero nickel boron coated FA BCG
Standard carbine buffer and spring
Troy Alpha forend
If memory serves it has an 8 twist barrel. Shoots great and is very accurate.
Unlike 223 builds the 300BLK is nice in that it usually doesn't need a heavier buffer or anything special.
Keep in mind though that not all factory ammo will cycle in all rifles, it doesn't indicate a problem with the rifle if it won't. I had a PWS 9.75 inch 300BLK that wouldn't cycle Hornady 208gr factory loads but it would cycle my 208gr handloads without issues, powder choice is very important with this cartridge.
Hopefully you are a handloader and again remember that just because there is load data in your book that doesn't mean your rifle with cycle it. I've tried loads that work great in my bolt action 300BLK but won't cycle my semi's.
Chinese ebay knockoff rail ladders. I think it was 4 pieces for $12. shipped.
I have some of those as well, they are a harder plastic than the good ones and don't fit quite as nice. They work though and are way cheaper
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Im not sure what im gonna do for the upper or lower yet. Im looking at a dd barrel 1:8 twist and a dd bcg. Probably magpul stock and grip cause i really like them on other peoples ar's and on my 870. As for a gas block i dont know what will work and fire control group not sure what i want. Am i missing anything else in this build>? Besides the for-end? Im trying to write up a price list for myself so i can order parts as i need Any more advice on uppers and lowers i like the spikes tactical lowers like the warthog but that alot of cash but i like the look. I like more block square looks but im going for best performance for cost. Its all alot to take in and im glad for everyone that been helping me so far!
Have a look at ALG forends and trigger packs. I have an ALG forend on my 9mm AR and I really like it. Also for the price of $170 you can't really go wrong. Their enhanced triggers are nickel boron coated and are a really nice single stage unit for only $77 at Tier One Armoury in Edmonton.
I would look at the Aero Precision uppers and lowers available at Saskatoon Gunworks. They are high quality and actually make uppers and lowers for a lot of other companies who simply do the final finishing work and put their brand name on them. The Aero parts are also available cerekoted in a few colors in case you want to build something a little different from the normal black rifles.
If you like Magpul grips I suggest the rubber coated MOE+, it's my favorite grip so far.
I like the Spikes Tactical parts as well but I don't think they're worth the extra money for something that serves no practical purpose.
I didn't have any problems with the NEA parts but wanted something a little nicer for the 300BLK and I used the NEA upper for a 16 inch 3-gun build I put together
View attachment 34536
NEA upper
NEA BCG
AP Customs carbon fiber forend $200 at Phoenix in Edmonton
Factory 16 inch barrel from a Bushmaster ACR that I had to open up the gas port slightly to get it to cycle reliably.
Optic will be swapped out to something more appropriate when I actually get started in 3-gun and I may swap the carbon fiber forend to something I don't mind bashing around a bit like the ALG unit.
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Im really digging the Aero Precision upper and lowers Ill keep searching around but right now that's my top choice and I like the ALG forends. Im looking for a full pic rail on top that's light weight and also not bulky I mean I probably will only have irons and an optic so I don't really see me putting much else on it maybe a flashlight or laser if I get bored but I wont ever practically use it. Keep the ideas flowing im bored and have the rest of the night to look up stuff im gonna waste money on lol.
im bored and have the rest of the night to look up stuff im gonna waste money on lol.Im really digging the Aero Precision upper and lowers Ill keep searching around but right now that's my top choice and I like the ALG forends. Im looking for a full pic rail on top that's light weight and also not bulky I mean I probably will only have irons and an optic so I don't really see me putting much else on it maybe a flashlight or laser if I get bored but I wont ever practically use it. Keep the ideas flowing
Here is my race gun with an NEA upper,
Im really digging the Aero Precision upper and lowers Ill keep searching around but right now that's my top choice and I like the ALG forends. Im looking for a full pic rail on top that's light weight and also not bulky I mean I probably will only have irons and an optic so I don't really see me putting much else on it maybe a flashlight or laser if I get bored but I wont ever practically use it. Keep the ideas flowing
Here is another of my 30 Calibers that has an Aero Precision upper with an ARP custom barrel.
