336-RC accurracy

[mikec177]

I am currently having trouble getting an older marlin 336 RC 30-30 to group. It will start out okay but after 3 to 4 rounds it starts to through shots all over and key holing.

I have cleaned the barrel several times with a bore brush. The bore is shiny and there seems to be good rifiling in the barrel. It has the marlin micro groove rifling in it. I have also tried several different types of ammo. The only one that seemed to work okay is the Remington core-lokt 170 grain. At least this one didn't key hole.

Can anyone help me with this problem. I like the gun and would like to keeep using it.

Thanks,

mikec177

 

[LeonCarr]

Mike,

What size are your groups? Are you shooting at 100 yards? Scope or Open Sights?

Does your rifle have the tubular magazine that goes to the end of the barrel, or does it go just past the forend?

I am thinking a couple of things. First, give the barrel a good cleaning with a good bore solvent like Shooters Choice, then use a copper solvent like Sweets 7.62 or Shooters Choice Copper Remover. Follow the directions until your patches are clean. Starting with a fouling free barrel eliminates one variable. Second, make sure that all of the screws are snug, especially the screw/screws on the clamp at the end of the barrel behind the front sight that holds the barrel and magazine together. That will eliminate one other variable, and with the screws snug when you shoot, the barrel vibration will be more consistent. If the rifle is scoped, double check the screws holding the base to the action, and the ring screws. if the base is loose, clean the bases and screws with alcohol, and use blue loctite on the base screws if necessary. Also, if the zero continues to wander, a bad scope might be the problem.

Also, when you shoot for groups, use a good stable shooting bench and good sandbags at the front and rear. Also make sure when you shoot for groups that the magazine of the rifle is fully loaded, because as you shoot the rifle, the point of balance of the rifle will go further towards the rear as the magazine is emptied, which can affect your accuracy and your point of impact.

Try to eliminate as many variables as possible, and hopefully your groups will improve. If 170 grain bullets are stable in your barrel and not keyholing, then the lighter 150 grain bullets should also.

Hopefully this will help. A good lever action rifle is a nice addition to any family .

Just my .02,
LeonCarr

 

[mikec177]

I have a new scope mounted on it. I was sighting in the new scope when this problem occurred. I was also shooting at 25 yards to get it to zero for 100 yards.
It does have a full length tube and I will check the screws and make sure they are snug.

All screws for the base and scope are tight. I checked them after mounting the scope and again when the groups started expanding on me.

do you think it could just be a matter of barrel fouling or is it going to be something more major?

Thanks for your input

mikec177

 

[LeonCarr]

I dunno...I have seen several rifles that went from buckshot patterns to under an inch at 100 yards after a good cleaning. One that comes to mind is a buddy's Remington 700 BDL .30-06. He brought it to me, said it wouldn't shoot. I checked all of the screws for snugness, took it to the range, and shot it. With Federal Premium ammo, it shot a 4 inch five shot group at 100 yards. To make sure it was not me , I shot another group that measured 3 3/4 inches at 100 yards. I got the rifle home, and ran a patch soaked with Shooters Choice through the barrel. The patch came out black and green, and the green was the same color as a John Deere Tractor (buttloads of copper fouling). I soaked it overnight in Shooter's Choice Bore Cleaner, and patched out and re-soaked the barrel over the course of the next day. After all copper fouling was removed, I took it to the range, and using the same ammo shot a five shot group you could cover with a quarter.

Try giving it a thorough cleaning, and see if that helps. I have heard that the Micro-Groove rifling can be a fouling hog.

If it doesn't help, I think a trip to the factory might be in order.

Just my .02,
LeonCarr

 

[Clemson]

New scope = Alarm Signal!!

Try a different scope -- even the old one if it functioned OK.

Clemson

 

[mikec177]

I'd like to thank everybody for their input concerning my problem. I took and cleaned all lead and copper fouling out of the barrel and put the old scope back on the rifle. I then took it out and shot it.

I was able to get decent groups using winchestere and federal 170 grain soft points. The only problem was that out of the ten shots fired 8 of them keyholed.

This leads me to believe that the barrel has been shot out of this gun. Do any of you know how much a new barrel will be and approximately how much it will cost to have it installed.

Thanks,

Mikec177

 

[LeonCarr]

Dang...I was hoping you were cured .

A good place to start would be www.marlinfirearms.com

A phone call to them (800-544-8892) will get you more information on the cost of rebarreling and/or shipping to their Service Department, hopefully it will be free .

Just my .02,
LeonCarr