Marauder tune

[knighted1]

Has anyone had any success with tuning their Marauder gen 2 in .25 caliber so as to deliver a heavy pellet in the mid to upper 900 fps velocities and still keep the rifle very, very accurate? If so what mods have you undertaken and what pellet selections?

[ezman604]

Gen I should be basically the same, I've not opened up a Gen II yet. Will soon.
But to get more power to push a heavier pellet will involve some valve work. Like opening the inlet side of the valve, necking the poppet, opening the transfer port and adding a lighter poppet spring. Then add a light weight hammer with internal SSG. Breech and barrel transfer ports will have to be opened to match the valve and new transfer port tube made. I have one that likes JSB 33.95gr Diabolo ammo and pushes them around 65fpe and very accurately.
SAFE & Happy Shooting!!!!
Dave
 

[hanleyfan]

I bought a war valve and no bounce hammer and got my marauder 25 cal. pushing 996 fps but the accuracy was all over the place, I started dropping the velocity until I regained the accuracy and found 935 fps was about as fast I could push the 31 gr. pellet and still have the accuracy I wanted.  I don't know if all marauders are the same but with my gun 935 is the best I could pushed the pellet and still keep my accuracy.

[ezman604]

Try some heavier pellets.

[knighted1]

All great responses. How do I do all that Dave.  Wow very technical!!

[ezman604]

Yep, it's technical.
If you don't have or have access to a lathe, mill and/or a good drill press, I would suggest you send it off to have it done.
Several I would recommend are Scott (Motorhead), David (Rocker1) and Travis of W.A.R. (oldpro). I enjoy doing these things WHEN I can find the time. But I'm not taking in any to do simply because I can't guarantee when I could get to it. And I don't like working like that.

[knighted1]

Ok thanks for the info

[LDP]

This is a mod im gonna do to my Mrod when shooting seasons over. I want to push 34 gr. JSB somewhere between 850 - 900 fps. Does anyone have a good link detailing the valve work?

[ackuric]

Am interested in the same, would love to buy a spare valve and send it off to someone to get ported. If anyone can provide this service let me know!!

[n2omike]

Am interested in the same, would love to buy a spare valve and send it off to someone to get ported. If anyone can provide this service let me know!!

You can buy aftermarket valves.  WAR (Wicked Air Rifles/oldpro on here)  sells an awesome valve.  You can also buy nice valves from hillairgun.  No core required.