Loose barrel?

[ofdscooby]

I'm pulling my hair out trying to find a good mono load for my 280ai and had a question. I recently helped out a couple buddies with developing loads for their pretty much stock 30-06's with hornady 165cx's and found a great load fairly easy with reasonable speed and great SD and it wasn't hard at all. One of my friends I shoot with threw out that maybe those stock barrels were a little looser than a match grade barrel that I'm working with in my 280 ai. Crazy theory or is there any merit to it. The load I found yesterday for the 06 was a 165 CX with 55 or H4350 and .030 off came out at 2855 avg 3/4 inch and an SD of 6. Rifle was a stock rem 700 bedded by me.

So I guess my overall question is would a "loose" barrel help with monos and how would you target trying to find a "loose barrel.

 

[Jud96]

No, I don't think a "loose" barrel would shoot any better than a premium match grade barrel. If you're having issues with finding a load, I would do a few things before pulling anymore hair out or putting anymore shots down range. I'll list the steps I take to evaluate a poor performing rifle. Trust me, if it can go wrong or cause frustration, it has happened to me. It happens to the best of us.

1- Check to make sure action screws are tight and torqued to 50-65 inch lbs.
2- Check to make sure the scope base and rings are tight and torqued to spec.
3- Check if the barrel is free floating and verify the barrel is free floating when the rifle is rested in the bags like you have been shooting it.
4- Make sure the barrel is clean and doesn't have built up carbon or copper fouling. Borrow or buy a Teslong borescope to make sure of this. They're cheap and awesome.
5- Make sure the bedding is stress free and not binding the action/barrel and check if the internal magazine box is free floating if it has one.
6- Check to make sure there's not built up gunk inside the bolt and in the firing pin spring.

If everything above checks out, I would try a different scope. If that doesn't solve it, then I would just try a different bullet. If you haven't already, run a seating depth test with the components you have been using. Try .010-.050 off in .005 increments with 3 shot groups. If nothing in that test shoots to your liking, then it's time to test new bullets or possibly dive deeper into it and check to make sure the action is getting proper ignition. It's not super common in match grade barrels, but you could potentially have a bad barrel. Before jumping to that conclusion though, I'd first check and try everything I've said above. Report back and ask any questions you have and I'll do my best to help and I'm sure others will chime in too.

Also, I'd like to ask for you to post the build specs on the 280 AI, the components you're using for reloading, and some pictures of the groups it's been shooting. Thank you

 

[ofdscooby]

Thanks that's a great list and super organized.
My gun is a a .280 ai on a trued rem 700 in a McMillan Stock and a bartline barrel and a Jewell trigger. Currently running a Leupold VX 3 6.5x20 that has worked very well for me on another gun.
I've done everything on the list except the bore scope.
As far as bullets I've tried
TSX
LRX
TTSX
E tips
Hornady CX's
Cutting Edge
Hammers
As far as powders
IMR 4831
RL23
H4831
RL 19

Etips with RL gave me amazing speed and single digit SD's but no accuracy

IMR with 140 TSX
Gave great accuracy but went to crap on hot days

RL 23 and the 150 CX's gave me some great accuracy but SD's of 40
(Probably my should have messed with length so
E more on this one)

Hammer 144's ? With RL 23 gave great accuracy and SD but could only stay on target out to 500 yards after then went haywire.

I'm ready to re-barrel to another caliber.
I have a PTG left hand Mag bolt and was thinking of a 300 win with those 165cx's or back to a slower 30-06 and the 165 CX's with H4350 that seems to be a good combo.

 

[Jud96]

How often are you cleaning the barrel? And what cleaning solvent(s) are you using? Also how are you doing load development for each bullet? You should be able to get good SDs with any of the powders you used, try seating depth testing on one of the better loads you have found and see how that does. That's a very good barrel and shouldn't be giving you problems.

 

[Bob Wright]

I'm having a lot of problems in the extreme spread velocity. I'm dropping down to the 130 grain Hammer to test it. The SAAMI 280AI chamber is throated very shallow and seating depth puts the 145 way deep in the case.
I have fought donuts with Nosler brass; went to Peterson.
It's a struggle, so tagging In.

 

[thatguyshm]

When I switch from lead core to solids I always clean to bare metal then run a few solids down before looking for accuracy.

I just picked up a savage ultralight in 280 AI. Box of ammo through it just to start the barrel break in, cleaned up and then using 145lrx and 6.5 staball I did a quick velocity ladder test, got up to 3130fps, but settled at 3000. Have it shooting about an inch. For a whitetail rifle that's good enough for me. I'd rather work on position shooting over taking a bullet diameter off my groups. If I wanna shoot further, I have other rifles for that.

Just my 2 cents. As far as loose VS not, I have a Christensen that is what you'd call a tight bore, which for that rifle means I use less powder to get normal velocity. If using factory 180gr listed for 2740, which I get in my mossberg 30-06, gets 2830 in the Christensen.

That's just my experience, hope you figure it out! Bartlein makes a heck of a tube

 

[cohunt]

Hammer 144s with rl23 -- good accuracy and sd's but only good till 500?

Sounds like a hardware or shooter problem.

Havent seen a "magical" distance where a proven load just goes wonky all of a sudden

 

[BillLarson]

if thats a stock rem.barrel rechamered to ai.
and it shoots 3/4" be happy.....

 

[Rosebud]

Hammer 144s with rl23 -- good accuracy and sd's but only good till 500?

Sounds like a hardware or shooter problem.

Havent seen a "magical" distance where a proven load just goes wonky all of a sudden

Was thinking same thing. Makes no sense.

 

[BillLarson]

Hammer 144s with rl23 -- good accuracy and sd's but only good till 500?

Sounds like a hardware or shooter problem.

Havent seen a "magical" distance where a proven load just goes wonky all of a sudden

I have seen bullets shoot great at 100 yds.but not at 300 and beyond... I believe because of bullet design.

 

[cohunt]

I have seen bullets shoot great at 100 yds.but not at 300 and beyond... I believe because of bullet design.

But at 100, 200, 300, 400, 500 then not further? That's how I took the ops info as he said its great out to 500 then goes to snot

 

[BillLarson]

But at 100, 200, 300, 400, 500 then not further? That's how I took the ops info as he said its great out to 500 then goes to snot

Bullet ballistics....

 

[cohunt]

Bullet ballistics....

Is that just like those bullets that shoot more accurate at 300 yards than at 100 yards?

 

[L.Sherm]

I've not seen Fed 215's and RL23 not shoot in a 280AI yet.
You haven't said what twist is your barrel or what primers your using.