AR-15 BS Thread

AMAZING... As far as groups I can get about an 1 to 1.5 inch group depending on Ammo also if I had more practice maybe better... ; )))

 

Thank u ; ))))

 

I ordered a Stag 8L and an Armalite AR10 a couple of weeks ago I can't wait to get them!

 

Merry Christmas to Adam! Keep us posted man.

Another question gang:

What are your thoughts on barrel length for the 6.8 platform? 18 vs 20 inch?
Would you expect a noticeable improvement in longer range accuracy with the 20, or relatively nominal?

 

I like to avoid the rapid cooling topic. Thermo-mechanical fatigue is a real thing.

 

Can you elaborate for me... Cuz I would actually like to know... Cuz I don't know much about it... And I can't seem to get a consistent answer.. You don't have to if you don't want... Lol

 

Rule of thumb on the 6.8 is 50fps gain or loss every 2 inches of barrel. I am building quite a few 18s right now but most of my builds (primarily for hunters) are 16" barrels. I do build occasionally 18" target crowns also.

You won't see an accuracy change with length only faster (in this case not much) and speed kills. If you're going to hunt pig and deer I suggest 16-18. If you plan on shooting the 140VLDs and extended range then 18-20. A guy up in Alaska did do a 24" barrel build and he was able to get considerably more velocity using slower burning powders which is usually counter intuitive to the 6.8. Factory loads saw no benefit as the powder was well burned up prior to the end of the barrel therefore resulting in diminishing returns. Right now the hot ticket for powder is R7 for 85gr bullets and AA2200 for 95s and up but a new powder is out that is being tested for the full range of bullets. r1200. Hope this helped. Also if your interested in an 6.8 upper don't hesitate to contact me or check my website. Hopefully ill have pics up of the uppers soon to.

 

Brett is full of knowledge

 

very interesting and great info. thanks again Brett

 

Sure thing.

Lol thanks. Oh and check out Quentin defense for that 80% question you were asking me about last night. I hear good things about them. No personal experience though just second hand from a couple other guys who do what I do.

Disclaimer: not my Data but not quoting as I don't know if he wants me to but seeing good things with this new powder.

A little testing with an 18" barrel
31.1gr 1200 85gr TSX loaded to 2.297 =apx 2900fps I had 2 groups that would have been near 1/2" if I hadn't pulled 1 shot out of each.
29.5gr 1200 110gr Hornady HPBT=2600fps
29.5gr 1200 110gr Nosler @2.295" =2600fps -This was not an accurate load, over 1"

None of the loads fired had any signs of being hot, I think I could go up .5-1gr.

 

http://en.wikipedia.org/wiki/Thermo-mechanical_fatigue

When you heat and cool something multiple times rapidly, you change the temper of the metal......

Sometimes this is good, sometimes this is bad...........

 

it looks like dad is gonna get the colt, now he wants a m1a to, he held one at the gun shop and it was love at first cheek weld.

 

m1a's are nice.

I'm buying a SOCOMII as soon as I grad college

 

Finally going to break down and get a Garand through CMP. The M1A made me think of that.

 

those are awesome too

I love mine

I shot at a ton of CMP events through high schools and competed in CMP sponsored shoots, but apparently that didnt qualify me to apply for one

 

I was on the Navy drill team. Not a better rifle out there for drill work. I love the SLAP they have when you spin them right and then the abrupt stop. I was always amazed at the balance that they have. Brings back memories. I could get that rifle spinning so damn fast it was a blur.

 

Good to know. When I went to clean it, it was all black again . Not sure what to make of that...

Well, I'll own up to my own stupidity. The reason I couldn't turn the hand guard anymore is that the top rail was getting caught on the block that the upper mounts to when you put it in a vice. Once I realized that, I removed it from the block enough to finish putting on the new hand guard. It fits perfectly and looks awesome!

Maybe I'm trying to be tacticool, I don't know. I do tend to try to go function over form. I read some pretty good reviews on the YHM, and that's why I felt comfortable going with them. Mine is only a carbine length, so I don't think I'm going to be hiding anything under it. I wanted a free float quad rail to mount a light and a sling mount for the front. I don't know why they made my rifle with only a sling mount on the rear. That seemed pretty stupid to me. I'm open for suggestions on the light though .

Thank you again for all your help. I really do appreciate it!

 

So does anybody have any advice on breaking in an AR-15? I just picked up a DPMS Oracle a couple days ago and didn't see anything in the manual on break-in procedure

 

Keep the bolt carrier with CLP for the first shooting session, then lube intermittently between cleanings. No need to go through any complicated barrel break-in on an Oracle.

 

Rev You need to handle an SPR to understand what they are about. The handle like a light DI rifle and they still produce outstanding accuracy. A lot of guys see sub-moa groups all the time. These barrels have been tested 1.5 accurate to 25K rounds. Most ARs don't deliver that accuracy when they are brand new, especially not piston ARs. So before you start breaking out graphs, the barrels are 20% lighter than standard barrels, while maintaining the same accuracy and 20K round longevity.