Is a Bushmaster with a 20in barrel and a scope accurate enough to be used effectively for long range varmint hunting?

I tried a scope on two different Bushmasters.  The first got 2" groups (Winchester 45 gr JHP), and was demoted to an Eotech.  The second got 1" groups and kept the Leupold.  FWIW.  I don't think you can expect to do much better than that with a regular chrome lined HBAR.

If you want to improve accuracy, get a better trigger and free float the barrel. If you do that, you can easily achieve sub-moa.

IMHO you need 1 moa to consistantly nail prairie dogs at greater than 300 yards. Especially in the spring.
But if your varmints are racoons, coyotes, jackrabbits, etc you can get by with a bit less accuracy due to a bigger target at a shorter range. But yeah, a better trigger and free floated bbl will do wonders for the gun and your confidence.

!!!!!!!!

I must have gotten a fluke, then, because my 20" Bushy VMatch, w/chrome bore, with a Bushnell 4-12X AO scope

and my Nosler Ballistic Tip handloads shot into a witnessed 1/2" last weekend.

I've gotten 5-shot groups in the .3" range (with no-one around), and they average in the .75" category.

I shoot 55 gr FMJ UMC yellowbox crap for the cases, and that is the ONLY way this rifle shoots over an inch from the bench! Only to about 1.5" max, tho.

Mind you, I had to lighten the trigger a bunch, and I drilled out the gasblock rivet, and holed the freefloat tube to allow for a Harris

bipod before this happened for me. A little bore-polishing probably helped, as well...I ran a bootlace through the barrel, and secured it

to 2 posts in the yard. Next, I added some small patches, almost too small to fit, then coated the rags with a healthy dose of Flitz, and

then run the barrel back and forth until the bore glows. Better than firelapped, IMEver-So-HumbleO!!

Regards,

FastVFR

I just purchased the Bushmaster Varminter and I love it. Loaded up 8 groups of 3 rounds each with different amounts and types of powder(Varget and WW 748).  This was the second group of 3.  It measured .285" center to center @ 100 yards using 27.3 grains of Varget.  Hornady 55 gr V-Max SP bullet and CCI 450 primer.  The scope was a Leupold 3.5-10 scope.  This weapon shoots like gangbusters.  

My BUSHMASTER A3 with a scope will shoot into an inch all day with WW 45 JHP, as long as I do my part!