On http://www.radomski.us/njhp/cart_tech.htm there are some info on chambers as follows for Bushmaster.
Chamber - 5.56 Bushmaster
Freebore - .0250 1 deg,
Lead Angle - 30 min
Comments - Info from Bushmaster (thanks!). These are one of the best out-of-the box barrels, and handle up to 80 gr bullets no problemo.
Is this correct?
Also do you have the
neck diameter -
freebore diameter -
as defined on http://www.clymertool.com/cgi-bin/reamer.cgi for the 223rem?
Any addtional info and specs are appreciated.
I'm mostly interested in additional info on differences between the varminter barrels
lr24v(pcwvms 24fvar9) varminter chrommoly and
(pcwvms 24-9ss) varminter stainless and the
dcm competition rifle barrel.
I'm currently using Bushmaster 16" heavy barrel with 20x scope, which is much better than I expected. On a good day 100 rds - 5shot groups averaging 3/4 inch or less at 100 yds with some approaching 1/2. Usually one out of the group opens it up by 1/4 or 1/2 inch. On less good days usually 1 inch average at 100 yds.
I hope to reach consistent 1/2 inch and eliminate fliers. Best bullets so far are 55 sierra hp and 69 sierra and commercial Win brass, but military brass opens the groups up 1/4+ inch.