Why is my gun doing this??
 

My Browning A-Bolt Stalker in 7mm Rem Mag is stringing its groups. It never used to do this. What is the cause of stringing?

Load Info:
Fed 215
Remington Brass
65.5gr RL 22
OAL 3.348"

The hole that is by itself is my very first shot of the evening from a cold barrel. Then the next two grouped in almost the same hole dead center and 1/4" higher. Then I moved my scope down 8 clicks and shot a 3 shot group that was .368", I let my barrel cool for a good 5 minutes then shot 2 more for an overral group of the evening of .683". As you can see in the picture there isn't any clover leaf, just a string.....What can I do to fix this?

RE: Why is my gun doing this??
 

Rammer how do other loads shoot?

If they all string thenpossible bedding issue.

If not then maybe just the load. 140gr Barnes TSX load does a vertical touching string but whenI throw another proven load it prints cloverleafs

ie: (same session - back to back groups with nothing other then allowing the rifle to completely cool down between shooting them)

RE: Why is my gun doing this??
 

Have you cleaned it real good lately ?

And has the crown on the muzle been bumped on something.
If a nick is on the crown it will make it shoot off.

Try cleaning it real good.

RE: Why is my gun doing this??
 

The browning a-bolts are glass bedded at factory and I've never seen a bad job of it yet. It is possible but unlikely. My vote is onbarrel stress causing it to "walk".

RE: Why is my gun doing this??
 

The gun actually probably has 1000 bullets thru it without a cleaning job.....So I might get ambitious one of these days and give it a thorough cleaning. My other loads all shoot nice lil clover leaf groups in one ragged hole. I might try maxing out the load with powder and maybe adjust the OAL a bit an see what happens. The powder an cases and everything are all the same lot. The powder is coming out of a big jug (I think 8lb bottle), can't remember for sure as its been since September since I did any loading for my 7mm.

I might work up some 139gr SSTs tomorrow, they always used to shoot very nicely for me. Then maybe I'll do a 10shot group or something an see what happens.

RE: Why is my gun doing this??
 

Well, I didn't want to state the obvious too soon ;)

Just goes to show that it isn't mandatory to clean every 5 shots to get acceptable accuracy....

RE: Why is my gun doing this??
 

Looks like I was baited by assuming you cleaned yer gun.

RE: Why is my gun doing this??
 

Rammer said his other load (s) don't exhibit the same pattern. So is cleaning really the culprit here? I'd think he'd see other loads exhibit changes vs just this one but maybe not. I don't know as I have never left my rifles more then 30 shots before the bore is completely cleaned.

RE: Why is my gun doing this??
 

I'm going to make this into a big experiment.

I did some looking thru my ammo cabinet and found that I have some 160gr Nosler AccuBonds loaded up, some 160gr Barnes TSXs, and a few other odds an ends.

I will shoot groups with all available ammo on seperate targets before I do a thorough bore scrub, and then I will shoot however many shots to foul ( ? ) then I will shoot groups with all the loads again and see whether the gun is more accurate with a dirty bore or a clean one.

Any other variables I should throw in?

RE: Why is my gun doing this??
 

I am not advocating this, but I know alot of shooters who have never cleaned the bore of their rifle. I always shoot a few shells before I sight my rifle in for the season. Then after I am where I want to be I do not clean the bore until the end of the season(unless a problem occurs). I always take a whole afternoon to sight my rifle in, and I wait 30 minutes between shots. I always want to shoot from a cold barrel if I am sighting in. When I get close I never move my scope without printing at least a three shot group.

Sighting in is where I think high quality scopes really shine. Low quality scopes when moved may or may not move the desired distance. When you move a Swarovski 8 clicks, and each click is 1/4 MOA, you can bet that your POI will move 2 inches. Good quality scopes make sighting in easy. I have watched my uncles over the years slap the side of their scope with their wallets to make sure their scope moved, and settled in(friction adjustment), I do not need to do that to a good quality scope. I have found that normally most problems are scope or mount related. Normally if it is rifle related the discrepancies are much greater. Tom.

RE: Why is my gun doing this??
 

When working up a load, I have often had a particular powder weight indicate vertical or horizontal stringing. It usually went away with increased or decreased powder charges. Since your rifle seems to group O.K. with a different load, I would recommend trying to adjust the load that's causing the stringing. I'm betting it goes away.

RE: Why is my gun doing this??
 

I reecently cleaned my cousins old Mod. 700 BDL in 30-06. He said it used to shoot very good with factory ammo. Then all of a sudden it just started slinging bullets everywhere. Problem is that he never cleaned the bore of the rifle, just the outside of the gun. After a very thouough cleaning of the bore he said it shoots better that it ever did. It did take a lot of cleaning, but that did the trick.

RE: Why is my gun doing this??
 

As a general rule: Vertical stringing is a pressure issue, and horizontal stringing is condition related. Eraticgroupings tend to be bending or scope mount issues. In BenchRest circles the thought process for vertical stringing is to either increase the powder by a click or two or decrease the charge depending on whether the conditions make you think that the pressure is high or low. for example if you did all your load development on sunny days that the temp hovered around 80 and this day the temp is a cool 60 then the assumption would be to bump the charge up a click or two etc.

I would further assume that since you stated that you haven't cleaned it in 1000 rounds that there is significant fouling. Significant fouling can cause increases in pressure, which might account for your stringing. That being said a Browning A bolt is far from a BR rifle, it is obviously a fine shooting piece though. I wouldn't worry too much either way if the group is stil under 3/4 MOA.

RE: Why is my gun doing this??
 

Well, since I am the worst person for cleaning rifles I did something today......Ordered up $330 of cleaning supplies, loading supplies, and a few other goodies from Midway today.

I should now be able to give all my centerfires the proper cleaning that they deserve. I might also have a new toy in the form of an Encore barrel coming from Eabco to play with :D

Delivery date on my cleaning supplies is 4/2, so sometime after that I will be able to post up results.

RE: Why is my gun doing this??
 

If its been that long since you cleaned it, might take that much in cleaning supplies to get it done...:D

My deer rifle gets cleaned after each season, or 2 boxes of shells, whichever comes first...My hunting buddy's gets cleaned whenever I do it, or he starts to have problems...(I do it then as well)...I don't believe he's ever cleaned a gun.

RE: Why is my gun doing this??
 

Thats kind of what I was thinking when I was ordering stuff up......I should be set now, just need to buy one of those nice Tipton gun holders with the next paycheck.