Home Forums Lever Action Central Marlin 336 Lever Actions 336 action work

I am not a lever gun expert. I inherited this one and wanted to have it tuned up and rechambered. I the Marlin 336 rechambered to .30-30 Improved, an action job done, and the trigger was supposed to be cleaned up to offer as light and crisp a break as possible with a requested weight of no more than 4-4.5lbs. The gun was also re-blued because it has quite a bit of surface rust and some light pitting on the receiver from where it had not been maintained before I go t it. It has taken over a year to get this thing back and I just opened it up and took a look at it.

It appears that the chamber was cut after the metal was re-blued, chamfered after bluing for certain, and there is light rust in the chamber and the top of the barrel "extension" for lack of better words. It appears to have rust leaching from the threads also.



I have cleaned as much of it as possible from the action as possible but have concerns about long term serviceability.

It feeds ok as far as I can tell given the two cast lead dummies he provided and I just sized and loaded the empty case he sent with a Hornady FTX and it seems to feed fine as well. The cases come out scratched to hell though. It doesn't want to eject empty cases unless I run the gun hard. Two questions about these cases:



1. In the top picture of the cases, why does the groove above the rim disappear when I resize the cases? Is the brass thin and soft or is the chamber oversized and is the cases being over-worked at the web?

2. What causes these dents just below the shoulder? They were on every case he sent.

The trigger is inconsistent. It will break with no creep about 60% of the time and about 40% of the time it has somewhere between a little and lot of creep. I primarily shoot bolt action and AR guns with good triggers. What is a realistic expectation for a lever gun trigger?

I want to gather some information here before I go back to the smith with my complaints.

I'm not a gun expert either, but it seems as though the chamber needs to be polished at a minimum and may even have to be re-cut( if possible). I think the chamber has a rough spot causing the dent and I suspect the throat needs to be re cut also. The neck of the case is being compressed when chambering a round and brought back to the proper dimension when you run it through your neck expander plug in your die. Since the work I've described can only be properly done with the barrel out of the receiver the rust issue can be resolved then also. You have a VERY rough chamber and a throat that ,I believe, has been cut too short or is undersized. I would take it to an experienced smith. That work should have never left the shop. I know what I've said doesn't make you feel good but that throat may even cause excessive pressure when a round is fired so best have it fixed.
good luck and good hunting

I believe the chamber needs to be polished as well as it looks much rougher than any of my match guns. I don't think the barrel was pulled when it was chambered but I do not know. It was supposed to be. Since it wasn't (my assumption based on the fact I think the rust is bluing salts leeching from the threads since I think was blued with barrel attached to receiver) I think the throat is pretty much the original factory throat. If you are basing your idea on the case neck of the dummy with the lead bullet, you are looking at a dummy that got crimped too hard and bulged a bullet. I think this happened because he didn't have .30-30 Improved dies since the fireformed cases he sent me had not been sized.

My biggest unknowns are what a good Marlin trigger feels like, why the case web smooths out the groove ahead of the rim, and what causes that dent (hitting the ejection port and thin brass?).

I haven't heard back from the smith but he shipped me the gun without charging me for it, just sent an invoice. Does anyone have a recommendation for a fix for any of the listed isses? Will polishing the chamber get rid of the longitudinal scratches on the case?

I went and shot the rifle today to see if I could replicate the scratches and dents. Cases do come out scratched but not dented. I think the dents below the shoulder may come from feeding them through the gun but cannot say for sure until I load some up and go try it again.

Sweet Jesus, brass gets scratches, it's a lever action. That other are bluing salts, like a told you.

Does the frigging thing go BOOM? Can you reload the brass and make it go BOOM again? Does it feed and eject?

Tracking. My issue is the chamber looks like this :

and the fired round is scratched differently than a parent cycled through the gun


Yes, it cycles and shoots. I need to test it more but my training cycle is busy right now. I know where the rust is coming from like you said but is it long term serviceability issue?

All's well that ends well they say. The gun shoots fine and cycles fine although there is some rust I can't quite get out and the trigger is a creey 5#. I finished fitting up the new Ballard style stock (I still need to cut it to length and fit a recoil pad and apply the finish) for it and took it to the range after installing the Williams TK receiver sight:


I shot a few shots off-hand at 25m to get it on paper then went to the bench at 100yds. The front sight is too short so with the receiver sight just barely clearing the receiver I am hitting about 8" above POA. It also has a bead which I don't like; I have never been able to get a sight picture that allowed for the hold I like. I prefer a blade and that is what I will replace it with since I prefer a 6 o'clock hold. Center holds work best for me with a bead front. Using a center hold I a five shot group, made a sight adjustment and figured out I needed a taller front sight. You can see them above the paper:


I switched to a 6 o'clock hold and shot three more (same three as on the square target but I had the reduced 600yds target pasted over it):

Looks like a fine shooter to me. Good looking rifle as well. I can understand your concerns on the brass marks and the chamber.

IN hind sight is the improved worth the cost???? I would like to see a fps comparison and trajectory comparison as well. I know now you can better neck size even thought you could theroretically neck size on the standard 30-30.

How are you fireforming the brass???

Where did you get your dies for the improved??? could the gunsmith alter the standard dies to improved using the same reamer???
Thanks ABLE

I can't say if it it's worth it in terms of velocity but I'm sure it it will be at least 100fps. The advantage will likely be mostly in headspace control, case life, and case growth.

I just shoot parent rounds to fireform. I necked down some .375 Win with a false shoulder but they needed to have the necks reamed.

I ordered the dies from Midway.

Being a rimmed case, doesn't the 30-30 headspace on the rim in either form the basic or AI form?

I resize rimmed and belted cases so they headspace off the shoulder. They both headspace off the rim or belt when virgin .

Can't see how changing the case shape on a rimmed or belted case would change headspace specs, since the case can only go as deeply into the chamber as the rim or belt will allow it to go.

Rim thickness and belt thickness is a QC issue and you can't do anything about it. You can control base to shoulder dimensions so it works, I promise.

Your trigger problem, is not right based on the three 336 rifles I have had worked on, they break at A nice 4 lbs. Nice looking 336A should be A great open sight rifle, are you working the stock fit so it is just right when you shoulder the rifle?

As long as you don't full-length resize the fired cases, wouldn't that accomplish the same thing?

Driftless,

Yes, I'm working the stock so that it fits me like a glove.

260,

I'm using an FL die to size cases so they bump shoulders back .002" like I do with an AR.

If you're going to shoot the reloaded cartridges in the same rifle, why do you full-length resize the cases? Why not just neck size? Once you trim the cases after fire-forming, you can probably load the AI cases 4 or 5 times before they stretch enough to require another trim, assuming that you're not running maximum pressure loads.

I get what you are saying and this isn't my first improved round. I full length size these, auto-loaders, and my practical match rifles because function is paramount. Also, the lever and autos don't have the camming action of a bolt.

I load for a few different 30-30, including a couple of Marlin 336s, and just neck size the cases. Each rifle has its own set of cases, so there is little chance of putting cartridges that were previously fired in and reloaded for rifle "A" in rifle "B". So far, I haven't had any feeding, firing, or ejection problems in bolt, lever, or pump action rifles. My 30-30 recipe includes Winchester/Olin cases, Remington 170 grain RNCL bullets, and H4895. I used to use IMR-3031, but decided to change to H4895 'cause I can use it in other cartridges.

I neck size in some instances but usually just in my LR guns that don't run the risk of getting filthy. My match guns get FL sized and I apply the same line of thought to most of my hunting guns.

For the .30-30 Improved I'm using Federal brass (bought 100 rounds of Federal Blue Box) and have another 75 pieces to fire-form. I just ordered a new front sight post when I got home from a week of training. I should have it installed by next weekend. It probably won't be until the last two weeks of September when I take some use/lose leave that I get much shooting done.

Once I get the rest of the cases fire-formed I'll start load development with the 160 FTX and either IMR3031 or H4895 because I have a lot and they seem to be popular for that chamber. I use IMR3031 in my Smokeless Muzzle Loader and H4895 in my AR and bolt practical rifles so either is fine with me. I have seen some mention of Varget and RL15 also and I have a lot of that too for match guns.