30-30 hits sideways

[Irascible]

A friend was over Saturday with a 1970s era 336 carbine in 30-30. He was complaining that his bullets were hitting the target sideways. Even factory rounds! I pulled the bolt and had a look at the microgroove barrel and could see no problem, it was even clean. It seemed to have some slight rust in the bore just below the muzzle, which went away with cleaning. I don't think that would cause the problem. Someone else claimed nicks in the crown would cause the problem. I couldn't see any but I don't think that would cause this severe a problem either. Any ideas out there?

[Bullshop]

Have you slugged it? It might be a 32 special no matter what the barrel stamping says. Thats one of many possabilities.

[nhrifle]

My first thoughts would be to slug the bore and maybe do a chamber cast to find out what's happening in there. Is the barrel tight to the receiver? Did the patch feel snug in the barrel when you cleaned it? The muzzle rifling might be causing that problem. Lever guns, even the Marlins with the easily removed bolt, generally get cleaned from the muzzle end even though most shooters know to avoid that. I have seen quite a few guns with great bores that had slight crown damage that would pattern worse than a shotgun. Marlins are good shooters so this one is worth looking into. Keep us posted with any findings you get.

[John Boy]

Any ideas out there? If the diameter of the bullet is smaller than the groove diameter of the barrel, the bullet will not obturate into the grooves and wobble down the bore. Another issue can be that the bullet is too hard and will not obturate into the grooves

[frnkeore]

If it's a micro-groove, I don't believe it would be a 32 spec. Mine used "ballard rifling". First slug the barrel, if it's .310 or smaller, I would suggest a 311466 mold shot as cast. What was the load he was shooting?

Frank

[Dan Cash]

Slug the barrel. Some Marlins have quite large bores. I have a 1950 vintage gun with a beautiful straigh and uniform bore; it is .3105. It does well with jacketed bullets but does better with a .312 cast bullet shot as a grease groove or paper patched to .3125 or so.

[missionary5155]

Good morning
Can't ya just here lawyer A at a "bored" meeting say, "We need to make the groove larger than the common projectiles to keep that nasty pressure down to avoid any possible laysuit due to a customer incuring injury from our product". Lawyer B responds, " I have heard the Army applauds good area coverage on machine gun ranges".
Sadly some "J thang" producers got the same idea and reduced their finished jacketed items by .0005. Now there is a combination that will produce great area coverage... far better than my M73 ever manage.
Mike in ILL

[Dan Cash]

Now there is a combination that will produce great area coverage... far better than my M73 ever manage.
Mike in ILL

Do you mean you were able to get a M73 to fire enough of a burst to be called area fire?????:)

[NSB]

Here's the big question....reloads or factory loads?

[Bullshop]

"""Here's the big question....reloads or factory loads?"""

I think the OP said both.

[Irascible]

Well, we got as far as trying a jacketed round down the bore. YUP, it's 30 caliber as marked. Other than that we have not had the time to check it further.