Crow magnum/theoben eliminator damage

My guess would be an eroded crown seal made it really slammy.

Are you refering to a rifle in a recent auction? I saw that also.

Unfortunately all too common. It's usually caused by one of three things.

1) Seals - as pointed out a failing piston seal will cause excessive recoil. The same goes for the breach seal.
2) Dieseling - usually caused by improper lubrication.
3) Over pressurization. This seems to be the most common. These are very high powered rifles but someone will always push things too far, especially when it's so easy to do.

No cheap or easy fix either.

When the seal erodes sometimes owners try to compensate by overpressurizing. Turns the ram into a jackhammer.
Keep looking. There's plenty of Theoben Eliminator wall hangers around. Guys never shoot theirs.
1 They're too heavy
2 They're too hard to cock
3 They're too expensive and the fumbly owners are afraid to gack them.

I LOVE them. Keep them at a reasonable power level and they are outstanding!
Absolutely beautiful, and wonderful to shoot.

I used to go to Airgunwerks...David Slade shop from time to time and he always had two or three like that laying around...Eliminators aren't an air rifle for a beginner or someone who wants to shoot "a lot", novelty items only as far as I'm concerned...now Theoben lower powered gas ram like the Evolution and SLR 98 are worth fighting for, tuned correctly shoot/cock like a dream. The same thing can and does happen to earlier SLR's with the cross bolt...I've seen it, also the SLR's will collapse the weld joint where the mag goes in due to overpressuring and or shooting WITH A MAG OR SINGLE SHOT TRAY "NOT" INSTALLED...I've seen several examples at Airgunwerks and RAW...not fixable although sometimes can be used single shot...I've talked to David Slade and Martin Rutherford at length about these issues...In my humble opinion Theobens in general and SLR's in particular should be retired and preserved...they won't out shoot an HW97 anyway but that's just me.