I test fired some 147 FMJ's yesterday that had been tumbled to clean off the sealant. Sorted by weight and overall bullet length, loaded in newly formed FC 11 .223 brass on top of 'LilGun powder.

My results were about as bad as some of the reports. Two rounds touching at 100 yds, the rest of two different charges were 5- 8" spread! This little rifle shoots subs and supers very well...but these bullets will go to a garage sale.

I didn't even try them in my 10.5" upper, didn't see any point in cleaning up another weapon.

quote:

Originally posted by TRshootem:
I test fired some 147 FMJ's yesterday...
Two rounds touching at 100 yds, the rest of two different charges were 5- 8" spread!

I've never seen such large groups from any AR of any caliber. Something more than just bullets may be the cause.

My groups with factory 300blk FMJ ammo at 100 yards:
ADI MSR 144 -- groups from 3.6" to 4.0" -- the worst FMJ performance in my SBR
Fiocchi 150 -- groups from 2.1" to 3.9"
American Eagle 150 -- from 1.2" to 3.2"
Magtech 123 -- from 1.6" to 2.7"
S&B 200 -- from 2.1" to 4.5"

FWIW, the worst group I've shot in 9 AR-15 223 barrels, with lengths from 14.5" to 24" is about 3". I think that was with Wolf or Silver Bear 55 FMJ.