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Discussion Starter · #1 ·
I have a 338mxlr that has the lever-popping-open thing going. I ordered new plunger & spring from Midway, then put a thin shim in the back of the plunger to compress the spring a bit more. The lever is now noticeably stiffer to open. When shot with this new plunger & shim off one of those weighted rests the lever still pops open. When shot off bags it doesn't pop open as often or as much, but it still opens a little probably 1/2 the time. when the lever opens the shots impact a little high, otherwise it's quite accurate. This is all occurring with the hornady ammo.

The first two boxes of shell I shot worked flawlessly and the grouping was very good. But then the 6 or 8 boxes shot since have all had the popping open problem.

My 338mx works like a charm with no popping at all.

I'm thinking of trying swapping out the entire lower tang/trigger/lever assembly with one of my other rifles to see if this fixes the problem. Is there any concern with doing this? Are the 336 and 1895 assemblies identical and can they be interchanged? If this works, I'd order one off the internet. I have also yet to try the Rem Core Lokt 250 gr ammo - maybe this will be different.

Thanks for your time,
John
 

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Discussion Starter · #3 ·
just regular ol' hornady 200 gr leverevolution.
 

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Discussion Starter · #5 ·
I'll give that a try and report back. thx.
 

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Have you checked your headspace? Excess headspace will make the lever pop open.

Rob
 

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I have a 338mxlr that has the lever-popping-open thing going. I ordered new plunger & spring from Midway, then put a thin shim in the back of the plunger to compress the spring a bit more. The lever is now noticeably stiffer to open. When shot with this new plunger & shim off one of those weighted rests the lever still pops open. When shot off bags it doesn't pop open as often or as much, but it still opens a little probably 1/2 the time. when the lever opens the shots impact a little high, otherwise it's quite accurate. This is all occurring with the hornady ammo.

The first two boxes of shell I shot worked flawlessly and the grouping was very good. But then the 6 or 8 boxes shot since have all had the popping open problem.

My 338mx works like a charm with no popping at all.

I'm thinking of trying swapping out the entire lower tang/trigger/lever assembly with one of my other rifles to see if this fixes the problem. Is there any concern with doing this? Are the 336 and 1895 assemblies identical and can they be interchanged? If this works, I'd order one off the internet. I have also yet to try the Rem Core Lokt 250 gr ammo - maybe this will be different.

Thanks for your time,
John
John

I had every problem ever known to lever guns that could possibly exist

I had a chap on here told me to bend slightly my lever ,,,,In a vice pad your lever and give it a shot with a bronze hammer ,It will be trial and error so go slow at first

Ken
 

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John

I had every problem ever known to lever guns that could possibly exist

I had a chap on here told me to bend slightly my lever ,,,,In a vice pad your lever and give it a shot with a bronze hammer ,It will be trial and error so go slow at first

Ken
That was what I was thinking, Since He has a 338 MX also He could try the lever from it and see if it did the same thing, Good call! :biggrin:
 

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Discussion Starter · #9 · (Edited)
after searching the forum, if i have this correct, the part of the lever that contacts the trigger safety block may be contacting first and preventing the plunger from fully engaging and holding the lever closed? And, this is the reason for bending the lever slightly?

Ok, I'll compare the two levers between my MXLR & MX, then fire the MXLR with the MX lever. This may be easier than I thought. Thanks, guys.

Rob, how can I check the headspace?
 

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Discussion Starter · #10 ·
As suggested by Ken and Dennis, the 338MX lever seats further into the lower tang than does the 338MXLR lever. I've attached pics of each for comparison: the step where the lever meets the lower tang, just fwd of the trigger, is much more noticeable for the stainless lever than it is for the blued lever.

So, i swapped out the stainless lever for the blued one and went up behind my property and squeezed off 3 rounds into a stump - the lever stayed closed for all 3 shots. I'll take it to the range this week and see what happens for the rest of the box. I'll report back when complete.

Hopefully this is the solution. Thx for your help,

John
 

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Try giving the chamber a good scrubbing. I had the same thing happen with a 336 recahmbered to 30-30 Ackley. I had about 300 rounds through it and my hunting load had always worked flawlessly. One day it just started popping open the lever with my hunting load. I had numerous people try to tell me that my load was too hot but I knew the same load couldn't suddenly cause the problem after the same powder charge, bullet, primer, and brass had fired flawlessly for over 100 rounds. I discovered that the shoulder was compressing slightly when crimping the bullets. You couldn't see it just with your eye but I could measure the difference with a micrometer. The rounds would cycle but the lever wasn't quite locking all the way. I discovered the problem when cycling handloads before I went hunting. As illustrated in the photo above check and see if there is a gap between the lever and the receiver with a loaded round.
If there is a burr in the chamber causing a lead build up or if it's just getting really dirty it might not allow the lever to fully lock.
 
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As suggested by Ken and Dennis, the 338MX lever seats further into the lower tang than does the 338MXLR lever. I've attached pics of each for comparison: the step where the lever meets the lower tang, just fwd of the trigger, is much more noticeable for the stainless lever than it is for the blued lever.

So, i swapped out the stainless lever for the blued one and went up behind my property and squeezed off 3 rounds into a stump - the lever stayed closed for all 3 shots. I'll take it to the range this week and see what happens for the rest of the box. I'll report back when complete.

Hopefully this is the solution. Thx for your help,

John
Hi John,
This string is a bit old now, so I don't know if you have resolved your issue yet, but here are a couple of things for you to consider before you go buying new parts or bending old ones.

1) There isn't really any set amount that the lever has to close in order to do its job. The amount of guard showing below the tang may vary from gun to gun, though your mxlr does seem to have some excess. Once the lever moves the bolt into battery its only remaining job is to lift the locking block completely into position. "Completely" means lifting the rear firing pin into alignment with the front, and locking the bolt into acceptable headspace. If both of these things are happening then your lever is closing/locking just fine.

2) It shouldn't require excessive plunger spring tension to keep the lever from popping open. I've never had to use a shim behind the spring. If anything, I usually decrease the spring rate to reduce cycling effort. The bolt's thrust should be acting on the locking block, which has a pretty shallow mating angle with the bolt recess. Very little downward thrust should be exerted during firing.

3) I have seen some levers that aren't quite fitted right regarding bolt control. The narrow forward tip of the lever (I call it the bolt control blade) has the job of moving the bolt fore and aft, but it is not the blade's job to lock the bolt in place. Once the bolt is 98% into battery the blade should disengage, allowing the locking block to shove the bolt forward over its last few thousands of an inch. On a properly fitted lever you can feel this disengagement. Right before the lever plunger enters the receiver the lever should suddenly lose friction, swinging up and down slightly without any contact internally, other than the pivot. At this point, control of the bolt is transferred to the lifter portion of the lever atop the trigger guard. It will drive the locking block upward, closing headspace, and bearing the brunt of any bolt thrust. However, if the bolt control blade is slightly too long it may remain in contact with the bolt, which can have enough rearward thrust to pop the lever open on firing.

One final note. I noticed in the mxlr picture that the trigger plate does not sit flush with the bottom of the receiver. Try loosening slightly the two rear screws (side and trigger pivot) that hold the bottom plate, then tighten the tang screw to draw the upper and lower tangs together. This may alter your situation slightly as well.

Hopefully this helps.
AD
 

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Discussion Starter · #14 ·
AD, thx for the explanation. i'll try loosening the screws and see if i can readjust the lower tang (trigger guard).

Buck9, that's +1 point for the bending-the-lever solution, which sounds like it has worked for several people.
 
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