I'm hoping someone can help me with a problem. I did my first glass bed job after doing a lot of research to make my 22-250 more accurate. I'm pretty handy and the bed job came out great after some trial and error. The barrel is still free floated as well. The loads that we used in this are 34gr of 4895 with a 60gr v-max. This is the load that has been shot out of this gun for many many years with great accuracy. When I took it to the range after the bed job, the bullet holes were slightly key holed.

It is my understanding that only two real factors are involved in key holing. A barrel twist being too slow to stabilize the bullet and a build up of copper in the barrel that could cause it to leave unstable. I have cleaned the barrel many times since the first time out after the bed job and let Hopes #9 soak well yet it still key holed this past weekend.

Also, the first 10 bullets out of the gun were not grouping well and had some fliers. It might have been me, but after the barrel heated up, I had a 4 shot group at a half inch with one flier making the group just over an inch. Can really cold weather alter the barrel's accuracy when free floated like this? I get the desired accuracy after a few rounds through it but still key holing.

Can a bed job alter the makeup of a good load? I can not see the physics of that being an issue but who knows. I just cant see what the problem might be. Please help!

If your bedding job is unstable the action could be rocking a bit, consequently pointing the barrel to a slightly different place.

No clue what could cause your keyholing though...try some stronger cleaner like Montana Xtreme.

I have heard of a bad crown doing this , but I can not confirm or deny because of no firsthand info. If it is a 1-14 the 60 may be pushing the overall length, but that does not explain the 34g.

try a 50 grain bullet and see if the keyholing improves....if you don't have any PM me your address and I'll send you some NC!

Most 22-250's are 1:14 and most won't stabilize above 55 grains. You might try loosening up your action screws and putting about a 1/16" to 1/8" paper or tape pad undet the barrel near the forend and tightening the action back down. The barrel may need a pressure point. If that works, I will tell you an easy way to install a pressure point.

quote:

Originally posted by Silent:
...I have cleaned the barrel many times since the first time out after the bed job and let Hopes #9 soak well yet it still key holed this past weekend. ...

Hey Silent, The Hoppe's #9 isn't strong enough. Smells great, removes Powder Residue, but just not strong enough to rip the Copper out.

Check the Gun Cleaning Board on down below this Board for lots of excellent Copper Removing info.

Once you do get the Copper out, it will probably return to shooting as well as it once did - at least no Keyholes.

Best of luck to you.

I'm with Airgun,

The 22-250 twist rate is made for 55 grainers and below. I'd try bullets in the 40s, 55grain max.

Best of luck.

I would also say that a in14 well not work well with bullets that heavy.

quote:

Originally posted by Moorepower:
I have heard of a bad crown doing this , but I can not confirm or deny because of no firsthand info. If it is a 1-14 the 60 may be pushing the overall length, but that does not explain the 34g.

I would inspect the crown right now. The second thought is the barrel is becoming worn, and as it fouls the bore tightens up, just a little. What is the round count? If you are seeing oblong holes at 100 yards... there is a problem.

I have never seen this first hand but have read numerous times how and i'm not saying you don't know how to do this but improper and vigorous cleaning can cause crown issues enough so the crown has to be redone.

Do you use a coated rod, a good bore guide like Lucas makes? I have been slapped on the hands many times by my dad for pushing the rod further out the muzzle than it takes to clear the length of the brush.

Again not trying to say you don't know what your doing but everytime I think I have something down pretty well I find out how little I know.

i get keyholeing from my 22-250 imp. with 55 gr.midsouth varment bullets.the barrel is 1 in 7 twist.it really sucks cuz it won't shoot the cheap ones but it shoots 60gr Part.and any bullet up to 90 grs like a house a fire.Good Luck

I've shot plenty of 63 grain Sierra and 70 grain Speer bullets with a 1:14 barrel, but those are semi-pointed bullets. If the rifle fired them before, but not now, I'd be inclined to think it was a fouled barrel.

Another factor could be some wear in the throat giving a free bore like condition which might allow the load to slow enough that it will no longer stabilize. That bullet/twist combination is marginal at best, and I'd bet a loss of 50f/s could make a difference. I'd be inclined to redevelop the load...

Plainsman456 wrote:

quote:

i get keyholeing from my 22-250 imp. with 55 gr.midsouth varment bullets.the barrel is 1 in 7

I can assure you that you are not getting keyholing with a 1:7 twist and 55 grain bullets. The twist rate coupled with the high attendant velocity of the 22-250 AI may be causing the thin-skinned projectile to come apart, but it is not causing keyholing.

quote:

Originally posted by Bobby Tomek:
Plainsman456 wrote:

quote:

i get keyholeing from my 22-250 imp. with 55 gr.midsouth varment bullets.the barrel is 1 in 7

I can assure you that you are not getting keyholing with a 1:7 twist and 55 grain bullets. The twist rate coupled with the high attendant velocity of the 22-250 AI may be causing the thin-skinned projectile to come apart, but it is not causing keyholing.

1 in 7 is for the heavier and longer bullets.

I shoot 60gr Hornady spire points out my 1-in-16 twist hornet so .... I have a friend who shoots 60gr boat tails out his 22-250 (presumably a 1-in-14). Something changed during or after the bedding. Possibly damage to the crown? Was the grouping checked immediately prior to the bedding job? Could anything else have changed, like the loading technique?

Thanks everyone for all of your help. I looked over the crown and nothing looks to be off with it. When bedding, I was careful not to do anything harsh with the barrel like pulling on it or anything of that nature.

Prior to bedding, it was shooting very well. Ive gotten 1 inch groups. It was never keyholing prior, though I was putting a lot more shots through it prior to bedding.

We have been shooting 60 grain bullets out of it for years. Talking with my dad, we are thinking the possibility of a bad batch of bullets that could cause a yaw. Has anyone ever had this kinda bad luck with a batch?

We have much less than a 1000 rounds through it. Can fouling build up that quick that it could be night and day?

I have found instructions to electricly clean the fouling. I am gonna try that. Has anyone else used this method of electricly extracting the copper from the barrel? Ive done similar things in chemistry class but it will be different with the set up.

I just want this thing shooting the way I know it can.

Thanks again for all the help!

i thought they were coming apart but moved the target to 25 yards because it wasn't hitting at 100.i have the target if you want i can e-mail it to you.i have some come apart with mt 243 i built but slowed them down and the gray cloud went away.plainsman456@yahoo.com

quote:

Talking with my dad, we are thinking the possibility of a bad batch of bullets that could cause a yaw.

Does that mean the bullets are not the same as the ones used previously that produced good results? Are they the exact same bullet design or just the same weight? I have found that some semi-boat tail bullets shoot well while a 'more' boat tail bullet yaws and sometimes tumbles. I have a 22LR that was producing non-round holes in paper. I cut off the suppressor threads after measuring and finding the end of the barrel was worn. This rifle now shoots small groups with round bullet holes. I suspect the muzzle wear was due to cleaning as the cleaning rod cannot be used through the breech. This rifle was never that accurate but was OK with some bullets. Now it is good with some bullets.

When you say 'key-holing', what do you mean? To me key holing is when a bullet cuts the paper traveling sideways. Oval holes are yaw - depending on how oval.

303Guy,

We were talking about the jacketed bullets possibly not being uniformly thick walls all around giving more weight to one side rather than another. I know bullet makers go to pains to make sure everything is quality, but possible some slipped through.

The bullts do not go in perfectly sideways, but some ovals can be a bit large. None are going straight in making perfect circles.

I have been using Hornaday 60 grain v-max. They are flat based.

quote:

Originally posted by Silent:
303Guy,

We were talking about the jacketed bullets possibly not being uniformly thick walls all around giving more weight to one side rather than another. I know bullet makers go to pains to make sure everything is quality, but possible some slipped through.

The bullts do not go in perfectly sideways, but some ovals can be a bit large. None are going straight in making perfect circles.

I have been using Hornaday 60 grain v-max. They are flat based.

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quote:

We were talking about the jacketed bullets possibly not being uniformly thick walls all around giving more weight to one side rather than another.

Silent
I would have expected 'duds' to be bullets with irregular cores rather than defective jackets. I do not know, but I would not expect defective bullets to show up as key-holing. I think that bullet yaw is not very marked. Have you tested these same loads at longer and shorter distances? You seem to have a situation that is of interest to many of us! (For me it's about learning!)

When I suspected my 22LR muzzle, I made up a set of brass 'guages' to 'measure' the bore with. These showed that the last bit of bore tapered open. This is not to say that yours is the same. I have been told that a worn bore at the muzzle end tends to throw the odd flyer at first then more and more. Some bullet styles will be worse than others and I have seen the yaw on paper.

Can you post a pic of the muzzle crown? Just interested in the style used by the makers. This is a pic of one of my rifles. It is not very clear but it is a sharply cut 11 degree with a protective shrowd type 'false crown'. It has no radius or chamfer. This makes it very vulnerable to damage! Hence the shrowd (which also happens to cover the step left when the bayonet lugs were removed).

Are you sure that your target is perpendicular to your rifle? A crooked target could make not so perfect bullet holes.

If not, it still sounds like copper fouling to me.

I've been using my Outers Foul-out II for many years. It's not quick, but it's thorough.

When you say you have shot this gun for years it tells me something.

You may have a shot-out barrel.

I have a 22-250 that I just re-barreled because of the same problem. It was key-holeing at 100 yds. also. I had used this gun for prarie dogs for years as a kid (20 years old, ha!) and it was always a strongly accurate factory rifle (Rem 700). We used to put up to 600 rounds in a day through it on a hot prarie dog town. The problem surfaced after I "found out about cleaning" the rifle and how clean barrels were most accurate.

Well, it seems the only thing making the gun shoot well was the years of fouling in the barrel. After I cleaned it (took 2 days to get the copper and powder fouling out) and came out with a clean patch it was off to go shoot some great groups! To my horror, the gun would not even come close to grouping as it once had and would key-hole every 5th or so shot as the barrel heated.

Savage makes their 22-250s in 1-12 twist rates which DO stabalize the 60 grain vmax. Is the rifle a savage

The rifle is an Interarms Mark X. W have been shooting it for years but not quite as often as you might think. We dont have prarie dogs up here, so ground hogs only get to see a handful of bullets sent their way when we get out. 600 shots does sound fun though.

The lands and groves dont look worn down at the muzzle and the crown doesnt look bothered at all. I do suspect the fouling has built up and am curious to see if there is a problem with accuracy after getting rid of the fouling.

As far as the paper being perpendicular, the holes from my new .25-06 went in pefectly.

Another question to the glass bedders out there. Could an action be too tight in the stock after bedding? This doesnt concern the oval holes in the paper, but just the accuracy on the first few shots before it warmed up. It was all over the place first, then I got down to half inch groups after a half a box of shells.

quote:

Originally posted by Silent:
...We have much less than a 1000 rounds through it. Can fouling build up that quick that it could be night and day?

Depends on the smoothness of the Bore and the material the Bullet is made from. I have some Original Fred Barnes bullets made from copper tubing which are very accurate for 6-shots. Then the groups begin opening. Clean the barrel and it is good to go again for 6-shots with those specific bullets.

Normal Gilding Metal Jackets do not Foul that quickly, but the Bores need to be cleaned properly and often if Accuracy is important to the shooter.

quote:

I have found instructions to electricly clean the fouling. I am gonna try that. Has anyone else used this method of electricly extracting the copper from the barrel? Ive done similar things in chemistry class but it will be different with the set up.

If you are planning to use the "Outer's Foul Out" like Dave mentioned, and if you follow their directions, then that is an excellent choice.

If you choose to use a Kludge Rig from the net, then you might still have good luck or ruin the barrel. Improper use of the Reverse Electrolysis Method can result in a Bore which is severely damaged.

Cleaning a Bore is not difficult(as is pointed out on the Gun Cleaning Board), but if done improperly, or not done often enough, can result in "Pits".

Best of luck to you.

What was the tempurature the day you were shooting? A bullet that is "stable" with a marginal twist at 70 might not be at 35. The 60 Vmax suggests a 12 twist with a 223, but your 22-250 at 14 should do the trick; however some barrel wear, fouling, a lower velocity load, and air temp all could lead to lack of stability. I am a firm beliver in not saying always or never with firearms- in 20+ years of work and over 10000+ firearms I have not ever had or heard of a bedding job causing bullets to key hole. I think a good copper remover, along with some black powder gel(it will remove "hard" carbon fouling)sholud solve the issue.

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