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Chatham · New Member

Hollow my name is Chatham. I'm new to the site but not to airguns. I'm looking for a list and possibly direction on improving my .22 disco. I have access to milling equipment and have been operating them for ten plus years.

I already have a mrod trigger. Now I need a guard.
Looking to see if anyone has some info on a p-rod hammer and spring conversion.

Suggestions openly excepted.

Thanks Chatham.

rsterne · Moderator

Have you installed a shim under the MRod trigger?.... It is intended for a thicker tube, and when installed on the Disco the sear protrudes 1/32" further into the tube.... This has in some cases made the gun hard to cock, the hammer to drag and cause inconsistent velocities, or even to break the trigger sear.... Once the trigger is spaced down 1/32" you shouldn't need to change the hammer.... A PRod hammer spring is shorter than the one in your Disco, you will lose performance using it....

The Disco is a great platform for modding.... If you plan on really trying for a large FPE increase, get the gauge block from a PRod.... It has a much larger through hole.... You will require a 1/8" NPT male to female extension to reinstall the gauge, the Disco gauge mount seals with an O-ring and is not tapered pipe thread into the block in the gun.... I have heavier hammer springs for the Disco if you want one, but they work best if you fill to about 2400 psi (the top of the yellow on the gauge).... While I've never seen a problem, that is beginning to push the limits on the valve retaining screws by dropping the safety factor below 2:1....

Bob

Chatham · New Member

I do have the shim and trigger. However they are not installed yet. After making the shim I planned on tightening the trigger mounting bolts to form the needed curve. This caused the first few threads of the stock bolt get damaged. The disco trigger lets the damaged portion of threads to pass through into the air tube, allowing for fresh thread engagement. I'll wait till i figure out if I need to order anything else from crosman before I mount the m-rod trigger.

As far as my interest in the p-rod hammer is for the RVA. Can I just use the stock disco spring?

I have hopes to get a shroud and Lothar Walter barrel. (Worried about messing a $100 barrel without asking for some experienced advice). Would a modified m-rod barrel be a good substitute?

Any opinion on the BNM breech?

Thanks for the fast feed back.

Chips won't fly till the research is done.

Chatham

rsterne · Moderator

Use a high quality 8-32 screw to "bend" your shim into shape.... and replace the Disco stock mounting lug with a new one (they are very soft and easily damaged) and then make sure you don't overtighten it....

You can use the stock Disco spring with most any RVA designed for a 22XX / Disco....

Shoot the Disco before you discard the barrel, most of them are quite accurate, some are amazing.... I have one .22 cal Crosman barrel that will hold dime sized groups at 50 yards all day long....

Bob

Chatham · New Member

Is lapping a barrel the same as reaming one? Please explane.

I saw a YouTube video with a man using an old bore brush inserted into the barrel. Then pouring soft lead into it to make a negative cast. Allowing to cool removing then applying an abrasive paste (what grit? I have 180, 320, and 600). Reaming as he called it. Does this make any since?

I have the stock lug on order along with a challenger trigger guard. Once the m-rod trigger is on, I think I'll stop here till I can gather what I really want out of this project.

Thanks for the welcomeing me to the forum. I look forward to chatting again in the future.

Chatham

Chatham · New Member

Is lapping a barrel the same as reaming one? Please explane.

I saw a YouTube video with a man using an old bore brush inserted

rsterne · Moderator

I have never heard lapping called reaming....

Bob

Chatham · New Member

My thoughts exactly.

Chatham.

Chatham · New Member

I found the YouTube video that sparked my curiosity. And I was wrong he wasn't saying reaming but lapping. To many YouTube videos in one session I guess.

http://www.youtube.com/watch?v=ml-9oLLKYsM&feature=youtube_gdata_player

Please tell me if this is a viable option.

viper2788 · Member

http://www.tko22.com/parts.html

TKO22 will tune your disco for $80. I was going to send my gun in for this, but then I realized I'm happy with my groups. Just out of the box with a 4-16x scope, I'm getting dime sized groups at 35 yds, and still under an inch at 50 yds. Can I expect much better?

Robw · Veteran Member

A Lothar Walther barrel will be the biggest factor in increasing the accuracy
of that gun. These barrels are far above stock Crosman barrels. Each one
has it's bore and rifling polished to a mirror finish! I have done this to
several and the difference was simply amazing! The barrel alone made
them in to a target arms. Smoothing the transfer passage will help with
consistency as will polishing all of the sliding surfaces and then burnishing
moly lube in to them.

Have fun with it, Rob.

Chatham · New Member

The Disco is a great platform for modding.... If you plan on really trying for a large FPE increase, get the gauge block from a PRod.... It has a much larger through hole.... You will require a 1/8" NPT male to female extension to reinstall the gauge, the Disco gauge mount seals with an O-ring and is not tapered pipe thread into the block in the gun.... I have heavier hammer springs for the Disco if you want one, but they work best if you fill to about 2400 psi (the top of the yellow on the gauge).... While I've never seen a problem, that is beginning to push the limits on the valve retaining screws by dropping the safety factor below 2:1....

Bob[/quote]

Would a standard brass nipple and coupler work as the 1/8" NPT male to female extention. Or would I need something stronger? My end goal is to install a gauge that has more of a p-rod or m-rod look. Along with the increase in the flow from the p-rod gauge block.