Posted: 4/20/2007 8:18:27 AM EDT
I got my latest lower and I am starting to piece it all together now. I am building my first 20 inch AR as a Varmint rig. I was considdering getting a J&T kit, specifically this one in a 20 inch 1-8 twist SS.
Bull Barel Kit
The only thing it wont have that I want is a Wylde chamber, if that is something I can do myself though or is not really needed then I will be fine.
What I really want to know is if anyone has built this kit from J&T and what kind of groups are you getting from it? Do you recomend anything else?
I have a 24" bull barreled upper from J&T.
I have been able to get 0.5-0.6 MOA at 100 yards using factory ammo and just a bipod. If I reloaded and/or used a monopod for the stock, I am sure I could get even better accuracy.
They are great barrels and more accurate than 99% of people will need (It's more accurate than they are).
I may be wrong but I tend to think that in a varmint rig one would mostly shoot .223 vice 5.56. That being said I cannot speak with authority on the varmint barrel but the Wilson air guaged HBAR is pretty accurate, and is chambered for 5.56 with a 1:8 twist, and did fine with Black hills 68gr HMBT, Winchester 45gr HP, and Federal Power-Shock 55gr PSP.
I put some mil-surp stuff through it too, but it just insn't loaded to as high specs, nor does it need to be.
The commercial varmint loads/ match loads were capable of sub MOA groups while the mil-spec Winchester Federal and IMI were consistanly 1.5 to 2 MOA loads at best with Winchester M855 (Q3269) grouping the worst.
Black Hills 68gr load turned in the best 100 group at 0.458 inches from sand bags on the bench.
Only load I got to try that was heavier was the Prvi Partisan 75gr. It showed potential, but during five shot groups it would open up from just under an inch to 1.25 -1.5 inches usually with two flyers.
It depends mostly on what type of ammo and shooting you plan on doing. The Wylde chamber is a nice option that could give some verastility. For range work and maybe some varmint and predator hunting the 5.56 chamber seems to give me the performance I was looking for with .223 loads and allowing me to practice with military surplus as well. J&T did a nice job assembling the Marksman upper for me and I'm pretty satisfied with their product.
You guys are awesome. Thanks!