10-19-2021, 10:38 PM
Squirrelmarm,
i too was after a light weight AR with as long a barrel as i could in 6.5 Gr.
my first AR upper was a heavy barrel BCA 24" 6.5 GR. which was what i thought i wanted. it shoots ok for a rack grade barrel. get good velocity out of it. but the rifle ended up quite heavy.
so i tried to build a light weight 6.5 Gr. upper. i wanted the experience of building my own upper, and i wanted something light and long barreled. I too, could find no light profile 24" barrels available. the longest i could find, excluding calling brux or other barrel makers and gunsmiths and having them make one, was the 20" Faxon Gunner. So that is what i used.
if i recall, i think the rifle & scope weight with the light upper on it came in ~8.25 lbs. much better than the 24" bull barrel BCA upper, as expected, but still not "light weight".
if you really want the weight of my Gr with the light upper on it, i can go get it out and weight it and give you a more accurate answer.
with sierra 85gr. HP and benchmark i came up with a load that would shoot 1 MOA and occasionally a bit better. Other bullets tended to get bigger groups, but nothing came in over 2.5 MOA.
a better shooter than i could probably do much better.
i remember a long time ago, when COLT was the only one making a civi AR and it was the SP1. i picked one up. of course no scope, but i don't think it weighed more than 6.5 lbs. was quite light.
years later i picked up a CMP match AR. they'd put lead in the butt and barrel handguards and had a bull barrel on the thing. if i recall it was around 18lbs. or so.
anyway, i could only get down to 8 1/4 lbs without a custom barrel, and that was on a 20" production tube.
I am not sure about VASCAR2's comment that speed decreases after 20". If i recall Mel's postings, his 28" tube got great velocity. perhaps what VASCAR2 's comment meant was after 20" the rate of velocity increase starts to diminish. My 24" HB does shoot bullets faster than my 20" light upper. to be precise i'd have to look it up, but if i recall it was in the 50 to 75 fps range depending upon bullet. i.e. speed did favor the 24" tube for me, but the gain over the 20" wasn't astonishing.
best of luck on your new upper build.
-tdbru
i too was after a light weight AR with as long a barrel as i could in 6.5 Gr.
my first AR upper was a heavy barrel BCA 24" 6.5 GR. which was what i thought i wanted. it shoots ok for a rack grade barrel. get good velocity out of it. but the rifle ended up quite heavy.
so i tried to build a light weight 6.5 Gr. upper. i wanted the experience of building my own upper, and i wanted something light and long barreled. I too, could find no light profile 24" barrels available. the longest i could find, excluding calling brux or other barrel makers and gunsmiths and having them make one, was the 20" Faxon Gunner. So that is what i used.
if i recall, i think the rifle & scope weight with the light upper on it came in ~8.25 lbs. much better than the 24" bull barrel BCA upper, as expected, but still not "light weight".
if you really want the weight of my Gr with the light upper on it, i can go get it out and weight it and give you a more accurate answer.
with sierra 85gr. HP and benchmark i came up with a load that would shoot 1 MOA and occasionally a bit better. Other bullets tended to get bigger groups, but nothing came in over 2.5 MOA.
a better shooter than i could probably do much better.
i remember a long time ago, when COLT was the only one making a civi AR and it was the SP1. i picked one up. of course no scope, but i don't think it weighed more than 6.5 lbs. was quite light.
years later i picked up a CMP match AR. they'd put lead in the butt and barrel handguards and had a bull barrel on the thing. if i recall it was around 18lbs. or so.
anyway, i could only get down to 8 1/4 lbs without a custom barrel, and that was on a 20" production tube.
I am not sure about VASCAR2's comment that speed decreases after 20". If i recall Mel's postings, his 28" tube got great velocity. perhaps what VASCAR2 's comment meant was after 20" the rate of velocity increase starts to diminish. My 24" HB does shoot bullets faster than my 20" light upper. to be precise i'd have to look it up, but if i recall it was in the 50 to 75 fps range depending upon bullet. i.e. speed did favor the 24" tube for me, but the gain over the 20" wasn't astonishing.
best of luck on your new upper build.
-tdbru