Just whats is done on Mac 1's Steroid tratment on the Sheridans?

[pipestone]

I read a lot on Tim's past services on the older rifles and was just wondering what all's involved and can one do it himself?



Thanks-

Dana

[avator]

LOL... trade secrets.

[ER00z]

I'm sure more than a few would like to have that information, Lol. The Steroid treatment was more than just power modification, the guns were also beefed up to handle the extra stresses of over pumping to my understanding.

The usual generic modifications to tune up all pumpers a little could help if the gun is retaining air, meaning a softer valve spring or two spring mod and/or a slightly stiffer hammer spring. The weak points will be in the pumping linkage and possible separation of the soldered barrel (from what I've read) from over pumping/achieving higher power levels. The steroid tune probably involved some trick porting and other valve modifications also.

If you have a stock Sheridan in good working order, I'd leave it alone (just my opinion). I'd pick a Crosman 362 or one of these up to tinker with...

https://www.fieldsupply.com/airguns/benjamin-variable-pump-air-rifle-177-cal-black.html

That being said, I believe these are among the last Benji 397S models being sold as new...

Either way, I wish you the best.

[avator]

I'm sure more than a few would like to have that information, Lol. The Steroid treatment was more than just power modification, the guns were also beefed up to handle the extra stresses of over pumping to my understanding.

The usual generic modifications to tune up all pumpers a little could help if the gun is retaining air, meaning a softer valve spring or two spring mod and/or a slightly stiffer hammer spring. The weak points will be in the pumping linkage and possible separation of the soldered barrel (from what I've read) from over pumping/achieving higher power levels. The steroid tune probably involved some trick porting and other valve modifications also.

If you have a stock Sheridan in good working order, I'd leave it alone (just my opinion). I'd pick a Crosman 362 or one of these up to tinker with...

https://www.fieldsupply.com/airguns/benjamin-variable-pump-air-rifle-177-cal-black.html

That being said, I believe these are among the last Benji 397S models being sold as new...

Either way, I wish you the best.

100%. I think a stock vintage Sheridan has greater value than any that have had modifications.
Tim won't even do the mods to a poor shooting gun so my thoughts are.. if you already have a great shooting gun why would you have irreversible mods done to it?
But at the end of the day it's like my grandma used to say.. "It's yours boy, wash it as fast as you want". 

[JPSAXNC]

The foundation of the steroid gun is increased valve volume. By increasing the valve volume more air can be stored at the same pressure with more pumps. So there is no increased strain on the pump arm and linkage.

[avator]

As mentioned, he also does a billet pump arm replacement to handle over pumping.

[Van]

   I bought the Mac1 steel billet pump arm for my 392.  It came with a solid steel Blue Streak style domed pump arm plug. It is so much more precise feeling with no side-to-side wiggle. I don't see how anyone could bend it pumping. I also got the adjustable pump rod but did my own valve work like putting an O ring seal between the valve and the barrel transfer port. I just ordered what I thought was the best parts of a steroid instead of sending the gun in for his valve work. I really like that those billet parts.