how to accurize a 30-30?

K

Kaylee

New member
So I have this old Marlin 336 I LOVE. Problem is, it ain't exactly a tackdriver. It was around 6MOA or worse with the buckhorn sights (my bad), and with a scope on it, I could cut that to around 3-4 MOA. Still not too hot. (I can pull about .7 MOA off a rest with a good scoped bolt gun, so I'm pretty sure it ain't me)

Any ideas on how to tighten it up a little, say to around 2"?

thanks!

-K
 
1. Make sure everything is tight.
2. Try shooting it single shot to see if it groups well with an empty mag. If it does, then you might see if there is some sort of problem with the mag tube attachment to the barrel.
3. Take off the forearm and see if there are any shiny spots inside the barrel channel which may indicate that the forearm is bearing on the barrel. You can carefully relieve those areas.
4. Check the crown. If it is dinged up it's pretty hard to get decent accuracy.
5. Check the rifling. The barrel may need replacing. Since these rifles often get cleaned from the front, it's not uncommon to find that the rifling has cleaning rod wear near the muzzle--especially with the micro-groove rifling in the Marlin guns.
6. Try some different brands of ammo. I've got at least one rifle that will go from a 6 moa rifle to a .5 moa rifle when I switch ammo brands.
 
First, try different brands/loadings of ammo. You'd be amazed at the difference it makes.

What he said. ;)

I THINK I've seen a fiberglass stock for them.

Not worth doing more than that to a lever gun.
 
Mic MacPherson (writes for Precision Shooting) plays with the Marlins and reports that with tuning they are often very accurate.

IIRC, trigger work and load developement were two keys. In lesser increments, (as mentioned) checking the barrel/magazine tube for rubbing and binding, muzzle wear, bedding the forearm, smoothing/adjusting the fore-end band, all play a part.

The scope is often a quiet source of trouble. To check, if you have a scope of known quality, it often pays dividends to mount that one on and see what happens.

Lever guns are often sensitive to benchrest technique. Try positioning the rifle with the sandbag under the reciever and your forward hand tightly grasping the fore-end.

HTH!

Giz
 
how to accurize a 30-30

MISSION IMPOSSIBLE !!!
The 30-30 in a bolt action can give considerably better accuracy than in alever action.

In a lever action about the only thing you can do is to make sure everything in tight and get the trigger worked on.

It won't be a tack driver but it might be acceptable.
 
well, the resident smith at the range I went to tonight said "bring it on in" so I did. He fired a few shots out of it, came back, and showed me a problem.

Apparently the locking block is worn, so the bolt pushes back a bit with each shot, opening up the headspace a smidge.. showed me the bulged primers as evidence of that, and showed me how the bolt has some play if you push in on it once it's locked up.

He says replacing said part would be relatively cheap, and would likely solve the lion's share of the problems. Sound like decent advice to y'all?

-K
 
If it's bulging primers with factory ammo, then it should be fixed. I'm sort of puzzled by his idea that the fix would help accuracy. He may something that I don't know.

The three keys to intrinsic accuracy are the three B's - bullets, bedding, barrel. Marlin barrels are pretty good. Bullets we addressed. (try several types - Hornady factory always gave me good results) Bedding is a bit tricky with a lever gun - but doable.

Fire control systems can always enhance practical accuracy. A good trigger and scope make it eaiser to take advantage of the intrinsic accuracy.

Madison - agree that a bolt gun can out shoot (genericly) a lever gun, but not by as much as you would think. The lever gun needs a bit more tweaking. When practical use is considered (caliber/bullet restrictions), the difference really shrinks.

Giz
 
With the extreme taper of a 30-30 shell casing, I would imagine a large headspace would be a very determining factor in accuracy.

Although, unless you're very paticular about what ammo you're using, the larger headspace will work it's way back into the equation.

The largest threat to my Win Mdl 94's accuracy with bench-rest is the fore-end hold. I get my best groups when I avoid touching the fore-end at all.

However, I've never seen anything better than 2-3 MOA with mine, so what'r you complaining about?!? Give that poor 12-point a fighting chance! :D ;)
 
Giz,

That gunsmith could possibly be onto something. If the block is backing up with trigger pressure the round is probably "floppin" down to the bottom of the chamber, only to be jiggled pretty violently with firing pin impact. That cartridge won't do the same thing twice with a loose lock-up. I fixed a little Erma Werke .22 lr Wagonmaster (lever action) that was shooting 3 in @ 50 yds the same way.
 
Since the 30-30 headspaces on the rim, a sloppy block would make a huge difference. Not only that, it would be unsafe to shoot. A case rupture or a blown primer is an accident waiting to happen.
I certainly would not want to be holding the rifle to my shoulder in the event of a failure!
 
Certainly fix anything that allows excess headspace.

But then, remove the foreend and the magazine tube. Shoot the rifle off the bench, resting the receiver (not the barrel) on sandbags, and see what happens.

Usually, the inaccuracy of lever action rifles of that type can be traced to the foreend and magazine tube binding on the barrel. This causes the barrel to perform differently from shot to shot depending on the barrel heat and (believe it or not) the number of rounds in the magazine.

If the barrel proves OK, then reassemble the rifle, relieving as much contact as possible between the barrel and foreend/magazine tube. I think the rifle's accuracy will improve significantly.

Jim
 
I've had a lever that would do better than 2moa. It was an out of the box Marlin 336CS. Nice gun.

If the lockup isn't tight, the accuracy will be nil. Same reason gunsmiths lap the lugs in bolt guns to improve accuracy. If things are moving around during the firing cycle, it's not likely that they are moving around exactly the same way every time.

Thanks for the info, Kaylee. A good reason to always carefully examine at least one fired casing during each shooting session, especially with older guns or guns you've never fired before.
 
Kaylee, my 2 cents worth since your gun is in pieces anyway, a couple of reliability/safety issues.

I just took my 336 apart for cleaning last week and noticed the big wear point on it wasn't the locking block but the ejector.

If your locking block is worn you might ought to get your guy to check the ejector for wear as well, just for funsies. A new ejector costs 10 bucks with spring attached and is arguably the part most likely to break in the field.

There is much debate about the 2 part firing pin but I like it as it provides a mechanical firing pin block if the locking block isn't engaged fully. Some people replace the firing pin with a solid one but that sounds really dangerous to me. A solid pin would make it easier to fire in a unlocked position. KABLAM! Bolt would become a projectile headed rearward!

Also, when he puts it back together a little dab of Loctite on the screws can prevent unpleasant surprises.

Oh, I almost forgot...5 minutes between shots on the range.
 
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