Given the same sights and shooter.
What size group could be expected from a Bushmaster carbine with a 16" barrel and also with a Colt target match with a 20 HBAR at 100 to 300 yards ?

Don't know about 300, but you should be able to get a 1" group at 100 or better.  That all depends on your setup, though.

Can you qualify this statement in any way? With what ammo? Scoped? Irons? From a bag rest?

 

Just judging each gun with everything the same, sights, ammo, bench rest etc. With all things being the same which gun would have the better accuracy ?

To be honest, you'll just have to go out and try different types of ammo with your rifles to see. Nobody has the answer.

 

My Colt Match HBAR has had a few thousand rounds through it and still holds near 1 moa with my dad's reloads, and that's with a national match rear peep from a solid bench.  Most of the few thousand have been with SS109 and PMC .223 however and they are not as accurate.  I've never tried those from a bench but prone with a good rest maybe 2" or a little more at 100 yards.

So long story short, good ammo works great with the Colt and if I ever get a carry handle scope mount I'd be interested to see if it could come up under 1 moa with magnified optics.

The AR is a relatively accurate platform compared to a lot of semi-auto rifles.   The barrels in those rifles themselves should be 1.5-2 MOA shooters assuming they're just regular chrome lined barrels (not stainless) and in good working order.  The Colt Match HBAR is obviously most likely to be the more accurate of the two, but by how much, I have no idea.

Bear in mind, most surplus ammo (M193, M855, etc.) is only good for roughly 2 MOA accuracy, so you have to factor that into the equation as well.

The biggest variables in practical accuracy are the ammo you're using, the optic you put on the rifle, and of course the shooter you put behind the weapon.

Long story short, if you have a capable scope, a good shooter and match ammo, I would expect those rifles to do 2 MOA or better (2" at 100 yards, 4" at 200, 6" at 300, etc.).

And like someone else said, you really just have to shoot the gun and figure out what ammo works the best in it...all we can really do is speculate based on what we've seen similar guns do.

Thank you for the replies, I appreciate it very much.
I am new to Ar 15's and am trying to decide which one to buy. I used to shoot regularly 30 years ago with other rifles and hand guns and am just getting back into it and reloading as well.

With just those 2 as choices,  I'd be inclined to buy the Colt and add a carbine upper to it later if you spend some time with it and decide you want a carbine instead of a rifle

What everybody else said about there being a lot of variables is true –––– you would think the heavy barrel HBAR would shoot circles around a carbine,  and it might –– but might not unless you find the right load

I have a handful of AR's ranging from an A1 rifle to a more modern M4 style DPMS –– even the lowly DPMS approaches 1 MOA with a couple of loads –– but will fling cheap XM193 all over the place    –– the old pencil barrel A1 gets in at 1.5 MOA using a 55 grain BArnes x bullet (barrel has a 1/12 twist and i dont use any heavier in that one)–– i had to mount an optic on top to accuracy test it due to my vision,  ––
    There just do not seem to be that many inaccurate AR's out there,  but quite a few inacurrate loads for them

I will probably get railed for this but I would go with the Bushmaster.  I don't care for the 20" and why spend the extra money just to have to Colt lower on a different upper.  Bushmasters are extremely accurate and are very reliable / durable.  You might want to replace the trigger because Bushmaster triggers kinda suck but the rifles themselves are more accurate than most of your "nicer" ARs.  The accuracy out of my Bushmaster with 62gr PMC is better than out of my cousin's PSA 20" (which is a good rifle) and he will confirm that.  Bushmasters do have the 1/9 twist ratio so if you are wanting to shoot 77gr or something you will lose a lot of that accuracy.

< Posted deleted, Warning sent - F >

< Off topic post removed - stay on topic and IM your off topic question to the appropriate person - F >

+1 This.  A very well articulated real world reply.

HBAR's seem really heavy and handle with all of the grace and finesse of a fence post in my opinion.  The Govt profile 20 inch and M4gery's handle like a really fun woman in my experience.  

Given the your two choices with the exclusion of all others I think you would be happier with the M4 style.

The 1st place winner of the 2011 Texas National Guard Rifle competition out shot all of the Colt A4's there with his personal Model 1 M4gery.  It very well could have been the factor of the Indian involved vs. the arrow, but the length of the barrel obviously wasn't a huge factor.

Welcome to the forum and let us know what you end up with and how you like it!

this sum's it up!

Thank you again for all the information, I appreciate it.
I am new here and already find this site to be one of the best with plenty of helpful people.
A 1000.00 is a good size investment for me and I want to be sure to buy the right one the first time.

Bob

Wow.  That's some pretty amazing shooting from 100 yards with iron sights.  1 MOA indicates and excellant rifle, ammo, and marksman combination.  you are doing better than about 99% of the shooters out there.  Keep up the good work.