Marlin 336, perhaps a serious problem? Need help!

[BoneDigger]

I bought a used Marlin 336 in 30-30. Today I took it to the range and tried to get the new scope zeroed. I was using Leverevolution ammo. I couldn't keep the shots in a 6 inch circle at 50 yards. I'd get close, then the next shot would be 5 inches off. I started cursing the new scope, then I noticed something. It seemed that the bullets were making a strange entrance hole in the target, amost elongated. Then upon closer inspection it looked like the bullets were literally entering the target on their side!!! It was almost a perfect silhouette of the bullet. What would make a bullet tumble like that?

The bore looks good on the gun and I can't see an issue on the crown, but maybe I'm missing something? Oh, and yes, I verified that it does say 30-30 both on the ammo and on the barrel.

HELP!!!

Todd

[Hobie]

#1 - crown ok?
#2 - slug the bore, oversize?
#3 - you're outta luck on the leverevolution for THAT rifle. Never fear, the factory 150s are just about as good...

BTW, just what vintage is this used gun? Pre cross-bolt safety?

[RKrodle]

Hey Bonedigger, I asked O.S.O.K. (Jac) just today if he had heard from you lately. We both put in for our doe permits for Bannister. On your problem with the rifle I would try a different ammo first, then go from there.

[BoneDigger]

Yes, this is a vintage cross-bolt model. Ibelieve it to be late 60s, but not sure. The crown LOOKS OK, but I'm not sure I couold spot a problem. The bore looks good to me. I'll try some different ammo, but I wouldn't think the brand of ammo would make a bullet actually tumble, would it?

I got a message from OSOK today and replied. I put in for Bannister this year as well. I have my fingers crossed. Lets definately make another hunt this year!

Todd

[TedH]

I'd give the bore a thorough scrubbing. Could it be fouled to the point where the rifling isn't gripping the bullets enough to impart the proper spin? That microgroove rifling isn't very deep to begin with. If there were a defect with the crown bad enough to cause that kind of instability I would think you could see it with the naked eye.

[horsesoldier03]

The first thing I would try is getting rid of that HIGH DOLLAR ammo! Get a box of promotion grade REM, FED or WIN and see how it does. If that doesnt work I would slug the bore and start shooting an oversized lead bullet with gas checks.

[Pete44ru]

I'd be willing to bet one of my best aggies that a previous owner has "cleaned" it too vigorously from the muzzle with a flexible rod ILO pulling the bolt & rear-ending it - thereby wiping out some rifling just inside the muzzle/crown, causing the keyholing.

whuddawannabet ? ?

If I'm correct, and that turns out to be the case, then the only cure(s) would be to either shorten the barrel beyond any damagd rifling & recrown it, or rebarrel.

It just might be a nice Winter/Trapper project.

.

[.45colt]

I agree with Ted,try scrubbing the barrel.last month I bought a beat up Marlin Glenfield model 30 made in 1969. I didn't think it had ever been cleaned judging by the outside of the gun. the first attempt to run a brush down the bore was bending the cleaning rod so I soaked it with shooters choice and let it sit for a day. it looked like a sewer pipe but after some work it came pretty clean. I mounted a 2x7 Burris compact scope on it and after sighting it in it put five factory Winchester 150's in 1 1/2" at 75 yards. I hope Yours works out as well.

[wm]

If it is a spent barrel you have the rifle I have been searching for.....the perfect candidate for a remodel.

Personally I would have bored out to .379 and rechambered to 38-55 as a trapper length barrel. My second choice would be to have it lined down to 7-30 Waters.

If the rifling is shot (or cleaned) out at the end of the barrel or if the barrel is bulged (I suspect a bullet might have lodged at the muzzle or some other obstruction causeing a bulge there when the next round was fired) you could probably trim it back to 18" or 16" and still have a lot of life in the old rifle.

Unfortunately that probably dows not help you in the here and now wiht opening day a few weeks away.

[76/444]

FWIW,....

I do not shoot 30/30,... but in my 444 I found Hornady Leverevolution flex tip to be anything but accurate and consistent. I had to go to the Hornady flat nose soft points.

Your prob may also have something to do with,... if it is a Micro Groove barrel. I know mine, as I said, didn't like LE ammo. Keyholing can be caused by a multitude of conditions,... from poor muzzle condition (s stated) to rifling not putting a proper twist on the bullet. That can be from a shot out barrel to undersized bullet. As many know, most Marlin bores are oversized in the micro groove examples.


I cut down the majority of used long guns I buy, never had this prob, but I don't know if that could be an answer for you or not!

[BoneDigger]

I don't suppose any of you guys are in TX? I'd sure like to have someone that knows leverguns look at it and make an assessment. None of the gunsmiths in this area are all that good (Tyler, TX), so one of you might have a better idea of what it needs.

WM, if this doesn't work out, and since I can get a new Marlin for around $400, I might sell this one to you for cheap and you can bore it out to whatever you'd like...

Todd

[AJMD429]

If the magazine tube iis putting strain on the barrel it can cause that - fire a group or two with the tube removed and see. If that's the cause, there are ways to put it back in place without it doing that.

[J Miller]

When cleaning rifles from the muzzle, use a muzzle protector. They're cheap to buy or easy to make.

Todd,

Go pick up a couple boxes of Remington or Winchester regular old 30-30 ammo and try that before you go tearing that rifle apart.

Also get a magnifying glass and look at the crown and the rifling at the muzzle. You'll be able to see any problems.

Joe

[O.S.O.K.]

Todd, I'm 18 miles south of Austin - but that's a far cry from your neck of the woods...

I have a 45 degree chamfer cutter and 30 cal bore guide that I can freshen the terminus of your crown - this never hurts and often helps accuracy. A small nick on the inside of the crown where the rifling stops could possbily cause what you describe but I don't think so.

For the bullets to tumble, there's something else going on. They are not gripping the rifling or there is something wrong with the bore near the end of the barrel - you should be able to see something like that.

The other thing is to mic the bullets - see what diameter they are - they just might be undersized and the cause of the problem.

Do try some other ammo though - if it shoots fine then I'd really look close at the leverrevolution ammo.

[BoneDigger]

OSOK, I'm actually going to be in Austin next week (week of the 5th-9th) and could bring it with me if there is anything you might be able to check for me.

I will definately try some plain old Remington bullets and see what I can find out.

Todd

[O.S.O.K.]

Dang - I'd be happy to take a look but I'm in Mississippi that entire week - on business and then to bow hunt with my buddy Smitty... figures...