Erma ELG 10 Winchester Rifle

[Phil Russell]

One week in discovered the risks of vintage collecting. Suffered what appears to be a catastrophic sear failure? Cocked the gun heard a snap and the bear trapped engaged. Had to manually disengaged the bear trap to release the cocking arm. Absolutely no engagement of the sear now. Yikes.

I do not know if this will help but I give below my experience of an Erma:
Unjamming an ERMA ELG10
I was given a non-working Erma ELG10. Problem was how to sort it as the underlever was fully open and would not shift. I sought a little help from Google and found my way to 'deejayuu' here on the BBS, who had stripped and rebuilt a ELG10 and was able to offer thoughts and an exploded diagram. Jules posts on the topic are available via a search. Thank you Jules. To cut a long story short we both concluded that the issue was related to the abt mechanism so:, with the frame cover out of the way I could see the compression cylinder stuck at the trigger end with a menacing compressed spring inside. Nothing would move... the trigger did nothing, the underlever was solid. So I strapped everything up, secured it in a vice and tapped out the abt pawl pin .... As I finally released my punch from the abt pin hole it all came free and the compression cylinder would return to rest. Part way there.
I removed cylinder and piston plus spring to look inside. This meant prising the compression cylinder plus part compressed spring out of the frame. Compression cylinder is secured to the underlever linkage by a pin but, in hindsight, did not need to be removed. Nothing obvious was revealed but I took a few bits out anyway to check against the parts diagram. Put these bits all back together, checked working of abt pawl and slide rod ... seemed OK. Assembled minus spring and after a bit of fiddling it worked ... piston retained by the trigger sears and the cylinder returning to base as the underlever was closed. Not too sure why but I can say that when I released the abt pivot initially, the cylinder returned to base complete with piston i.e. the piston had not engaged with the sears. Maybe this was related to a part I had removed and replaced ...part 1021 on the exploded diagram termed a locking bolt. It is an angled flat plate with a small tab at one end. It locates on a spring such that it pivots. My first success at locating it on its pivot just did not seem right as the tab rode on the trigger mechanism with the tab doing nothing. So I figured that the tab should be located under a corresponding part on the trigger (1027). I relocated it to do that and as the trigger was pressed, the part 1021 rocked with the trigger. Fitting it was trickier but seemed to work.
Next problem was refitting the spring. I had not removed barrel etc as the pins were very tight and I made no impression on them. So how to refit the spring? Unlike deejayvuu, my valve compressor tool was not long enough and was a very awkward fit with the barrel in place. In the end, after about 2 hours puzzling and trying various ways, I set the action in my spring compressor rig, lashed it down and prepared to wind the spring into the piston with the cylinder at a slight angle to allow spring to clear the action. After much trial and error it worked ... a long bolt with about 1cm of thread in the end of the spring guide, stopping on a nut. Winding spring in slowly (goggles and leather glove time), it worked and once I had the guide over the end of the action I managed to slip the edge of the spring guide onto the top of the action and keep it there with a gloved hand while I released tension on the long bolt, removed it and then hand pressure (squeeze) let me slip the guide fully into the recess on the action. Job done. In all about 4.5 hours .....Rifle now works. I can only imagine that in the factory they used various jigs to assemble it.

Was the original jam related to that part 1021 being incorrectly fitted? I do not know as I did not record its position in the jammed state but as it was just too easy to fit it in the wrong position, maybe it was the cause. Maybe the rifle had been apart and put back together incorrectly such that it cocked to engage the abt but not enough to engage the trigger sears... I will never know. But it works now.
Out of interest, the piston washer is 'plastic' of some sort and did feel tight in the cylinder until the last couple of mm when it became looser. With AA Field it gave low 400s. Other pellets that came to hand were not so good, even lighter ones. Given the small compressed air volume I think this is not too bad even though I have read some reports of 600fps achieved after squirting oil into the cylinder.

Hopefully this may, at some time, be useful to others.

Cheers, Phil

[45flint]

Not sure my issue is the same? Are you saying that with your gun the piston spring stayed compressed? On mine the spring is not compressed, I can cock it in the normal manner but at the end of the cocking travel nothing catches and it backs off to the bear trap. I can release the bear trap by hold the wedge down with a punch and slowly release the cocking arm back to the normal closed position. The sear just does not engage. I assume I can that the cover off without fear of the spring being released?

[Phil Russell]

I fear I may have complicated / confused matters ... sorry. When I bought the said rifle I remember it being jammed solid with the cocking lever open so my account is/was my tale of sorting it out .. and yes, the spring was fully compressed.
good luck with your problem ..
Cheers, Phil

[45flint]

I fear I may have complicated / confused matters ... sorry. When I bought the said rifle I remember it being jammed solid with the cocking lever open so my account is/was my tale of sorting it out .. and yes, the spring was fully compressed.
good luck with your problem ..
Cheers, Phil

I appreciate your thoughts. Given my gun is not compressed I don’t feel the need to rush in. Waiting for a good day when, I’ve calmed down and got the time to make sure I don’t bugger up the screws as I get into it. Should be easy to see why the sear isn’t catching just hope against hope a part isn’t broken cause I have no machinist skills. In the mean time it still looks pretty!

[deejayuu]

Hopefully just the sear spring.

[45flint]

Unfortunately it’s was very easy to see the problem, a broken piston sear cone. Worse case for me, from a shooter to a wall hanger in a week! Does show the risk of vintage collecting. Just a shame these are such interesting rifles. Does make me wonder if I should stay with older prewar guns that seem to be built like tanks.

[Phil Russell]

That is a great shame. I wonder if anyone on here could make you a new piston rod? Some people seem to make new rods for their short stroke / long stroke conversions so may be able to help.
If not, and this could be a totally daft idea but could a rod from another rifle do? Would a Walther LGV/LGU rod come close? Or one from an old Original gun that uses the 3 ball trigger? Or even dafter, could the end of the rod be tapped to accept a bolt which could have its end profiled to suit?
Cheers, Phil

[deejayuu]

Definitely fixable. Take heart!

[45flint]

Definitely fixable. Take heart!

I will ask around here know some good repair guys that have the expertise and equipment just don’t know if they will take this on.

[deejayuu]

Bribery works most times

[45flint]

Just had my go to guy here in the US walk away. This has got to be the most depressing part of this hobby.

[Leonardj]

Have you removed the piston from the gun to see how the latch rod is held in place? (ie - welded, pressed, threaded, etc).
If the rod can be removed from the piston, the repair might not seem so daunting to whomever will be doing the work.

Worst case scenario, is that the old rod will have to be drilled out, and the new rod suitably re-attached.
All is not lost, it is just one of the challenges of the hobby.

[deejayuu]

Here's the piston/rod out of one of ours. Took it out to check dimensions and 'cos can't leave burgerhall alone!
7.8 mm dia x 95.5 overall. End plug, 5 mm thick, pinned but may be blind. Rod may be pinned or, threaded/pinned, even machined from solid but seems wasteful/unlikely. Now if we only had the broken one
Maybe pistol men know of similar as replacement. P.S. forgot to say leather seal soaking in Neatsfoot 'cos someone asked.

[45flint]

Had a major collector I first meet here in the US at the Alm auction earlier this year, text me today out of nowhere, that he had a NOS Erma piston he would sell me. What are the odds of this?! Story may end happily after all. Power of the Internet to connect people.

[Shed tuner]

that's brilliant flint.

One suggestion.. I chopped 2 coils of my mainspring - I figured it was too hard to cock, and maximum power wasn't really a concern. power did drop a foot pound or so, but cocking is now much easier, it's nicer to shoot, and wear and tear must be proportionately reduced also.