Maximus Prime

[FuzzyGrub]

I see.
So it is larger diameter than the steel breech.

The Mrod shroud for sure, because that is slightly larger than the width of a prod breech.  I suspect the 3/4" OD of the Prod shroud is also larger than steel breech, but don't have any of those to measure to be 100%.  Anything smaller than Prod shroud, won't help much in its required function. 

[Monkeydad1969]

Man, I just caught this one.  Looks interesting.  You answered the M-Rod trigger question for me.  Now my Power Maximo will have a friend.  I got a .180 exhaust Cothran PowerHouse valve and installed into a Disco tube.  Then I just moved my Maximus .177 upper to said tube.  Over 1000fps.  Took it out yesterday and I really have to slow it down.  Just shotguns all my ammo, even the Piledrivers which are 21gr.  Going to cut down the 13XX spring even shorter.  I hope to get it to dial in next time I take it out.  Shown with Paris 'D' LDC and my "Have a nice day" bolt handle.





The Monkey

[Monkeydad1969]

I see.
So it is larger diameter than the steel breech.

The Mrod shroud for sure, because that is slightly larger than the width of a prod breech.  I suspect the 3/4" OD of the Prod shroud is also larger than steel breech, but don't have any of those to measure to be 100%.  Anything smaller than Prod shroud, won't help much in its required function.

Yeah, you'd need a breech riser to get a shroud to fit with the steel breech.

Joe

[Buldawg76]

Been under the weather a few days so just getting caught up with this thread. Yes to use either a Prod or Mrod shroud on a steel 13/22xx breech will require a breech riser or taller repeater style breech for the shroud to clear tube.

Yea I have had the same issue with the gauge block rotating when installing it and have yet to figure out any way to stop it from rotating in the tube that works well. I use a piece of PVC pipe to push them into the tube and found that if the pipe has a square end it helps prevent the block from turning if the pipe is kept straight when pushing the block into place. I also put my hand that is not pushing with the PVC pipe at the end of the tube so I can apply pressure to the pipe to prevent it from being able to slip and push the block in past the gauge hole accidentally and cut the o ring. I have not cut any o rings since doing it that way and the block does not rotate out of alignment easily either.

Those Cothran valves are really making tons of power in the guns they are going in and require a different approach to tuning than a regular valve since from what Rsterne has found they don't have a normal curve or knee on the strings but rather have a plateau with a steep cliff that is very narrow in terms of the adjustments so that its more of a on/off type of knee in the curve. It takes very little changes to fall off the plateau of the curve with the Cothran valve but well worth the effort once tuned properly.

Mike

[K.O.]

Man, I just caught this one.  Looks interesting.  You answered the M-Rod trigger question for me.  Now my Power Maximo will have a friend.  I got a .180 exhaust Cothran PowerHouse valve and installed into a Disco tube.  Then I just moved my Maximus .177 upper to said tube.  Over 1000fps.  Took it out yesterday and I really have to slow it down.  Just shotguns all my ammo, even the Piledrivers which are 21gr.  Going to cut down the 13XX spring even shorter.  I hope to get it to dial in next time I take it out.  Shown with Paris 'D' LDC and my "Have a nice day" bolt handle.





The Monkey

sounds like it just might work  for the 30g BBT with a .22 Max upper...

[Monkeydad1969]

Yeah, not my first rodeo with the PowerHouse valves, just for what I want.  Should be fun.

Joe

[K.O.]

wonder how the bombs n nasty 27g destroyers work out of the new Barrels..?

rodeo... dad rode with Cayse Tibbs a few times back when he was fresh off  the ranch in 1950's... ...  true tho

not your first, deja voo...

3/13/15 thread..

https://www.crosman-air-pistol-owners-forum.com/board/index.php?topic=15109.0

[FuzzyGrub]

The regulator has hit the states, and the shroud and hammers will be shipped this week.   

I still have to figure out a trigger guard.  The NP one was too small, and one from a Gen II Mrod stock, is too big.  Time to find some metal to bend. 

[farmerjoe99]

The regulator has hit the states, and the shroud and hammers will be shipped this week.   

I still have to figure out a trigger guard.  The NP one was too small, and one from a Gen II Mrod stock, is too big.  Time to find some metal to bend. 

as far as I know the only trigger guard that fits is the challenger, which requires modding the stock on the maximus, and threading a hole in the trigger pack
I should have some sample 3d printed ones in a couple days if you would like to try one?
But I look forward to seeing what you come up with.

[Monkeydad1969]

wonder how the bombs n nasty 27g destroyers work out of the new Barrels..?

rodeo... dad rode with Cayse Tibbs a few times back when he was fresh off  the ranch in 1950's... ...  true tho

not your first, deja voo...

3/13/15 thread..

https://www.crosman-air-pistol-owners-forum.com/board/index.php?topic=15109.0

My Sumatra carbine loves the Destroyers, the Bombs are to inconsistent in quality and it shows when shooting them after 20yds. 

Thanks for the info on your dad, pretty cool.

Joe

[Tater]

as far as I know the only trigger guard that fits is the challenger, which requires modding the stock on the maximus, and threading a hole in the trigger pack
I should have some sample 3d printed ones in a couple days if you would like to try one?
But I look forward to seeing what you come up with.

That's a great idea of a new product to market. Good thinking.

[FuzzyGrub]

The regulator has hit the states, and the shroud and hammers will be shipped this week.   

I still have to figure out a trigger guard.  The NP one was too small, and one from a Gen II Mrod stock, is too big.  Time to find some metal to bend. 

as far as I know the only trigger guard that fits is the challenger, which requires modding the stock on the maximus, and threading a hole in the trigger pack
I should have some sample 3d printed ones in a couple days if you would like to try one?
But I look forward to seeing what you come up with.

Joe, I'm going to be out of cmmision for a few days.  😩

I'd be vary interested in what you come up with.  I was starting down the road to mount direct to stock vs trigger assy.

[Machinist]

Farmer Joe

That's great.  Not many choices for trigger guards out there.  A strong, light, affordable trigger guard, that drops right in and fits like a glove!

Steve

[39M]

Hope everything's alright.....

And thanks for letting us follow along with your build. It's looking to be close to what a lot of people would want in an all-around PCP rifle.

[farmerjoe99]

Ok, if they end up working(it make take a retry or two) I'll send you one to get your thoughts on.

I have one that I just have to make a couple tweaks to for the discovery but that is pretty straight forward compared to the maximus  ...

In other news, I got in a maximus valve today so now I have to reread this thread so I can better understand what you did with the valve.

but I was a bit surprised to just how different it is from the disco valve, not a bad looking bit of bling either:
P_20170314_175949 by Joseph Snyder, on Flickr

[FuzzyGrub]

As a few of you know, had an "event" early this week that will slow me down some.  Luckily, pcp builds are not considered "heavy lifting". 


I received the Huma reg and rebuild kit:





I have installed it and run a couple of stings.   These strings were slightly low on the power I am wanting, and low on the shot count.  I am concerned that the plenum is too small.  It is wasting allot of air with the lighter poppet spring and still using the oem hammer weight.

[FuzzyGrub]

Also received my package from David today.   


Shroud:


He sent me three hammers of different weights:



For those that know David, he always includes other goodies. 

Here are a bunch of things that screw into Prod shrouds:


and some useful tools for the DIY work:


Thanks yet again, David. 

[Buldawg76]

Now that's what I call a goodie bag for sure. David is always going above and beyond for the forum members.

mike

[FuzzyGrub]

You would just have to drill a new t-port in the tube. The Breech would sit a little bit forwards from the end of the tube.

I sold my disco tube, so can't check that.  If the breech is moved forward, then you will have some modification to the end cap which the breech screws go into.  It would also change the trigger pack screw location. 

When I had it, I stared at it for a long time, and there are just so many interrelated parts that it "scared" this DIYer away.  The max tube was relatively easy. 

[FuzzyGrub]

I had set this down for a bit.   I had to make a front air stripper shroud mount for the 0.480" LW barrel.   I turned a 25 cal Mrod one down in my Dewalt lathe.  To fit the barrel had to add some soda can shims.  There is not much room between the barrel and ID of shroud.  David is making me a more permanent one. 

Accuracy seems to be good, so far.  A starling fell out of a tree at 45yds with one shot, this last weekend.   

Now that the shroud is on, noticed noise that was a leak at the bolt/barrel o-ring.  Ordered some 90D and metric oversize O-rings.

I have some stock mods to do yet:
- Make plug for gauge hole
- Fill stock cavity with foam
- Need about a 1/4" cheek risor
- Get and install 3D DiscoRus trigger guard