Hello,

I recently traded off my Bushmaster Dissipator 16" w/ JP trigger and some other accessories, and picked up a (lightly) used Bushmaster V-Match 16" carbine.  The only modifications I've done so far is I put on the 3-way adjustable butt plate that I had, and the Sierra Rite-Pull grip and the slip-grip pull extender.  All mainly cosmetic and/or to make the gun fit me physically (I'm 6'5" 290# or so)

Initially I just stuck an ARMS riser and my 30mm Redfield ESD red-dot sight on it and sighted in at ~50 yards in the back yard, figuring this would work well for 0200 AM coyote calling.

Today, though, I decided to see what this gun could do.  I've heard all these stories about 'dime sized groups' out of stock out-of-the-box AR's, regardless of brand, but especially Bushmaster.  Hell, that's part of why I got the thing.  So I dug up one of my spare scopes, a Leupold 6.5-20x50mm LR scope w/ an extremely fine target dot reticle.  For reference, the dot is a smidge bigger than a .30 cal bullet hole at 100 yds.  So optical clarity and aim point was not an issue ;)  I shot off the same setup I use for my heavy varmint guns, a Sinclair front benchrest w/ windage adjustable top, and Protektor rear bag, filled w/ heavy bag sand.

Everything seemed great, but the best I could do (and trust me, I tried) was ~2" at 100 yds!!!! WTF?!?  I shot both Blackhills 52gr moly match, and Blackhills 68gr moly match, w/ pretty much the same results.  Different POI, but same sized groups.

Right now,  a Jewell trigger is looking pretty likely, since the factory trigger is about 5-6#, and very gritty and creepy.  But I can't imagine its the only factor here.  It's not the only heavy trigger I've shot, though I must say, it is far and away overall the *worst* trigger I've ever used.

Any thoughts or suggestions would be greatly appreciated.

nuk

I hate to break it to you, but that ain't bad for a milspec chrome barrel. Maybe it isn't quite MOA, but it will do it for ever. For real accuracy you're going to need a match grade barrel. Back in the `70's when muscle cars ruled the streets, there would always be the clown that "burned tires" on wet pavement, as if that was impressive. My slogan was "Everybody has a race car in the rain.". Most claims of dime sized groups from a standard AR are just wishful thinking. 2MOA is actually pretty respectable for a 16" chrome barrel.

I have a Bushmaster V-match as well, but with the 20".  My best (read "consistant") groups out of that barrel were about 1.25 to 1.5 MOA at 100 yards.  And that was with good ammo on a good day.

I agree about the trigger.  It absolutely sucked.  

Since then I've modified it with a Shaw fluted 24" stainless bb, a Jard trigger (@1.5lbs - sweet), psg-1 style pistol grip etc... etc...  Let's just say I like accessories.

Not much left of the original V-match to speak of, but it shoots better than I do. The trigger was the first to go (first stoned then replaced), the barrel second (saving it for a rainy day as well).  Those two items helped considerably, as did the target practice I did in the process of making my baby "perfect".

In my experience, gus is right about the milspec chrome lined barrels.

There was a production problem a couple of years ago with Bushmasters (mid-late 1999?).  Evidently many went out that had the barrels overtorqued.  Bushmaster "might" be able to tell you if your serial number is one of those.  Something else to consider.

Hmmm... this is kinda interesting, because over on the Go Go Varmint Go board, a dude just got roasted in flames because he called a regular board member a liar claiming dime sized groups w/ a relatively stock Bushmaster 16" carbine. Lots'o people jumped in w/ relatively small groups (as in, w/ pictures of the targets), but it seemed like most of them had modified triggers, etc.  But I'm pretty sure almost all had factory barrels, whether they were Bushmaster, Rock River, or DPMS.  Figured I would ask here to see I was grossly overlooking something before I fanned the flames again on that board.  It was pretty ugly there for a while.  Glad I wasn't that guy ;)

nuk

[sniper]

Try using JB Bore cleaning compound on that barrel. get a dewy wrap style jag and lap the snot out of that bore. and scrap that trigger. I like JP Enterprises triggers, single stage just like a bolt gun. also try ammo loaded with 55g Nosler ballistic tips. my hand loads shoot .25in with a chepo Oly barrel

Hello nuk,
My free floated Bushmaster Dissapator will shoot the Winchester Q ammo about 2moa with iron sites or with a scope. I hoped for better.

However, after testing several reloaded bullets I discovered it would shoot a ragged hole with Winchester 64 grain PP. Success, and with a bullet I would have chosen if my barrel would only shoot one bullet really well. (This is with a benchrest setup that removes most shooter error. This is one good way to test ammo and barrel, IMHO. Now practice remains for the shooter to shoot as well as the rifle.)

Therefore, I agree that chrome barrels are not the most accurate barrels. But, I know that my chrome barrel shoots at least one bullet as a ragged hole. My experience shows that if you reload and are methodical you can find a sub moa bullet for your barrel.
Hope this helps you.

Prior to tweaking the above rifle, I was able to pull off 3 round dime sized groups once in a while.

Anyone can get lucky.  By consistant I mean 5 rnds +, and the ability to repeat it.

I need to get more into reloading.  I've met several like Goad in that they can tune a load to the firearm.  Sounds like good advice to anyone wanting accuracy.

Ok, dumb question here.  How likely is it that I'm going to accomplish anything beyond wearing myself out trying to 'lap' a hard chrome lined barrel???  W/ a normal unlined barrel, I could see your point, but these chrome lined jobs are designed to withstand machine-gun fire, for chrissakes.  Not trying to be a smart-ass, just not following you here.

nuk

Nuk
You're gonna do the trigger thing anyway, and I think that will help a lot. In the meantime, try as many different brands/weights/loads as you can find. Sometimes, though not always, you can find a combination that your gun just loves. If that doesn't help, it may be time to venture into reloading

It would also be worthwhile to slug the bore and mic the slug. Take a chamber cast and compare the results to SAMMI specs. Get an empty case neck-sized just enough to fit a bullet snugly, barely seat the bullet in the case, and chamber the round. You'll be able to derive the distance the bullet has to jump to engage the rifling. There are many factors contributing to accuracy. You might try the same question over at the 'Competition' folder for further tips.

nuk,
I'm not saying it will turn this barrel into .25 shooter but it dose help. JB is a mild abrasive lapping compound and hard chrome will polish! I have made several Colt barrels shoot .75 all day long and for the $15 bucks and some elbow grease it will cost you what do you have to loose?

nuk,
try some of there Nosler BT ammo shoots good in the ar
[http://www.georgia-arms.com/index.htm]

I saw the flame on the other board and think that some people just get pissed when their firearm or their own skills just plain suck.
Anyhoot, clean the living snot out of that 16" and try several types of ammo, not just two. I'm lucky because I reload and have some damn fine ammo made up.
Oh yeah, dump the heavy stuff. My V-match 16" works best with 40-55gr V-max under either AA2015 or H322. Couldn't get any of the heavier loads (factory) to shoot much better than 1 1/2.
My trigger sucks as well, so I make sure that I lube it right before using it as I don't have the dough right now for a fancy trigger.
I get great groups of around 3/4" with 23gr H322, 55gr V-max in R-P cases using (Oh my God) Lee dies.
For factory ammo, I've had excellent results with Federal 50gr HPs and even had good luck with the Winchester "White Box" though they didn't like to feed.
Good luck
Rob