Diana 460 T05 Cocking Arm/Linkage

[kondorthe2nd]

Just came across an '07 460, T05 and after reading all of the depressing threads about the weak cocking arm assembly, I was wondering. Are there any aftermarket kits or ways to bolster this shortcoming?

Thanks

[Roadworthy]

I believe Diana has gone to a more robust cocking linkage on their newer 460.  I don't know when they made the transition.  If the cocking linkage on that particular 460 is too wimpy you should find a current replacement from Umarex to be the fix.

[longhunter]

Get ahold of Mike at flyingdragonairrifles.com.

[Mark 611]

I have owned a few T05 460mags and never had any problems with the cocking arms!!! I think it has a lot to do with how the person who is cocking the rifle and how they have treated the rifle while cocking it! IMO if someone has slammed the arm down to get the rifle cocked this is where the problem lies! those rifles need to be cocked gently and not horsed down!!!!! some people are not strong enough to cock these rifles correctly and jerk the lever down as hard as they can to cock them!!! and this will damage the rifle over time!!! I have a current T06 and its sweet!!!!!

[Sfttailrdr46]

There is also the TLC approach ie; clean , deburr , polish and lube that will always improve the cocking process

[kondorthe2nd]

Thanks longhunter. I will. I have no problem cocking this gun but I have been and will continue to use a slow, smooth stroke. Good workout never hurt anyone. I really like this rifle and it's super accurate. I just don't like how the cocking arm is kind of loose and rattles somewhat. I use 3" shoot and see's at 60 yards and I can keep 'em all in the black...green I mean. When I get too tired to cock it and shoot accurately I'll take a rest and then grab my trusty model 27 and relax.

[HectorMedina]

Just came across an '07 460, T05 and after reading all of the depressing threads about the weak cocking arm assembly, I was wondering. Are there any aftermarket kits or ways to bolster this shortcoming?

Thanks

In my, and DIANA's, tests, it takes about 50 kg of force to bend the old style T-05 cocking levers. Still, it happened.
My theory is that people used their WEIGHT to cock the gun with the buttpad resting on the ground. Sure way to damage ANY airgun.

Here is a side by side comparison of the old and the new levers (T-05 is on bottom):




See if you really have a T-05 lever, and if it is crooked, send it to me and I will replace it with a T-06 one. You pay only the shipping.

HTH




HM

[kondorthe2nd]

Thanks Hector. Been out of town all weekend. I'll look at the gun when I get home tonight. Shot it all weekend and it worked just fine. Did a slow, easy cocking stroke. The spring in question stayed where it was suppose to as well. I think what may have happened the first time is that I either didn't have it closed all the way. Or perhaps the pellet was only partially seated. The gun seems to prefer JSB 14.35 gr pellet but I have to be very careful when loading because they fit very loosely in the barrel. Crosman Premiers aren't too bad in the accuracy department and fit really, really tight. Actually have to push them in quite a bit harder. Was going to order a few more tins of the JSB's but I'd kind of like to find another pellet that's just as accurate but fits just a bit tighter than the JSB pellet. Any ideas. On the plus side the 14.35 gr JSB pellet is averaging 807 fps while the 14.3 Crosman's are getting 795 fps.

[HectorMedina]

20 ft-lbs is a good performance level if the gun is not dieseling at all.

Perhaps you can try the 16 grainers JSB's those are available in different head sizes. Being a little longer, they may hold onto the rifling better, and if the head of the pellet gets engaged in the rifling, then you might even see some improvement in efficiency.
The Crosman Premiers are designed to seal at the head, that is why they fit much tighter.
You also need to ensure that the breech is closing positively. Cock the gun and then try to move the exterior of the compression chamber. If you can, you need to change the breech closing spring to a stronger one.

Personally, I always fit a re-inforced breech seal in all 460's and that helps a lot with the consistent seating of the pellets in the chamber.

Good luck and keep us posted!

[kondorthe2nd]

Morning Hector. When you say compression chamber do you mean the silver cover that slides over the chamber once the action is closed?

[HectorMedina]

Mark;

It is NOT a cover. It IS actually the compression chamber that slides with the piston, it just so happens that the piston stays BACK when the rifle is cocked and with the compression chamber moving forward, the air gets pulled into the space and can then be compressed by the piston.
In automotive terms it would be the "Cylinder" as related to the "Piston" that is the travelling part.

;-)

HM