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lorraine · Member

Hey guy's look on facebook under Don Cothran and see his new valves for the M-Rod! . It uses the factory weight spring and factory hammer and pulls off 200+ fpe with eaze, Big power and cocking with one little finger and can also be adjusted to how far it opens on shot cycle. It opens super easy at 3000-3500 PSI. His goal this year is 1000 units at about $150.00 each!. I for one am getting on his list before the sales get to far along. This valve with a Bob Sterne SSG would make a MONSTER as these valves are made for little to no preload on stem at rest. I can see a new .257 in my lineup after I finish my Cothran .308. WooHoo!

lorraine · Member

The larger I.D bore in the top part of TP port is .375 and the lower I.D near the valve stem is .250!. The TP port in air tube needs to be opened up to .375 from .265 so you can run up to a .250 TP to barrel. also the throat bore is a big .365 this is a air mover!

AirGunEric · Site Admin

Cothran didn't design this valve, a guy named Sean ("SMP" in some online forums) did a couple years back, but got hung-up with family BS and disappeared. I had one in my hand and he customized a few rifles for people with this valve design in late 2013/early 2014.

lorraine · Member

Don cothran has been building his powerhouse valves since before 2009! and at least 3 years before that in prototypes . Your facts are wrong.

AirGunEric · Site Admin

That is truly amazing, especially seeing as how the Marauder did not appear in the market until 2011.

In case it was missed, we're not talking about all his valves- we're talking about the Marauder valve.

rsterne · Moderator

FWIW, I've never seen a valve by Sean that uses a balance piston to reduce the opening force, but it might have been around before I met him a few years ago.... It would be surprising that he never mentioned it to me, if that was the case....

On the other hand, I never heard any mention of the PowerHouse (Force Reduction) valve until about a year ago.... although according to the article in Airgun Hobbyist Magazine Don was working on prototypes for 3 years before he released it for sale.... The version released last year was for the Disco, not the MRod....

That magazine is no longer published, AFAIK, but if someone has the original where the article was published, that could settle when the valve was announced.... it was on page 36....

http://www.cothranmachine.com/PowerHouse%20Valve%20from%20October%202013.pdf

Bob

lorraine · Member

I you look at dons shot gun it was made in 2013! the 22xx powerhouse valve was in his 2260 builds long before we guys started to plant them in discos! These valves have been off the radar to most main stream builders as they are made to hunt large game with bullets! . It is in a class of it own!. I talked to don today and the valves have been around since about 2009. If you read the write up it also says at it's printing he was planing this larger valve build back then. He also said that a small handful of valves were sold to people in canada. I received the new powerhouse m-rod valve today to look at and will be sending it to our friend Norm at DiscoRus to play with in a .25cal to start with 49gr bullets! . If we can get Bob Sterne to talk him into a 30cal tuneup things will get fun!. Heck Lloyd has 30cal clips that will hold 68gr lead. LORRAINE Naughty

rsterne · Moderator

Has he been making valves since 2009, or working on the PowerHouse valve since then?.... I can find NO mention of it on any of the Forums prior to March of 2014.... 3 years before that would be 2011, not 2009....

None of that matters, of course, because Don brought it to market and it's a brilliant idea.... Nice to see that he is ready to release it in a larger size....

Actually, there is a 75 gr. BBT that will fit Lloyd's mags....

BTW, I notice the magazine article was from Oct. 2013.... and Don is quoted in the article as saying he had been working on the design for 3 years and had built 8 prototypes....

Bob

lorraine · Member

Your right it does not matter! you think the m-rod powerhouse is a step forward! Don is now working on shifting the basis valve spool and making a valve that is pointed at the .40cal-the 72cal brothers! the throat is going to be alot larger than .365 then it is now and aimed at barrels 28"+ in shot cycle valve dwell . Things are going to change here quick in BIG BORE WORLD ! . You guys save all the pellets you have shot into that plumbers putty as us big boys need to cast bullets!!!!!!!! Mr. Green

lorraine · Member

Now that I know that a newer HYPER valve is going to to be tuned to the .40+ cals ,I got out my yellow TJs sheet and looked at .40cals and WOW! What do you choose ! seems the bore with the most choices! WHAT GIVES????? Shrug

lorraine · Member

Bob is there a twist rate that you can choose in .40cal on TJs sheet that you can zone in on with different weight lead and fps and a fpe goal?.I had way better results with a slower 1 in 20 308 Tjs than the faster twist he has listed. I know that the cothran twist in .357 is the barrel that YOU HAVE TO ASK FOR at TJs as it is not listed on the sheet as Don owns the tooling and TJs is using with don's consent . I'm starting to find the lower twist rate barrels to show higher FPE and less fussy as to say unswaged BUT close to bore slugs. I GOT HUNTER SUPPLY .30cal 118gr FPs in .308 size not .309 unmatched and unsized to group under 1.160 @ 85yds, 10 shot group at just around 1020+-8 fps with 6 feet off crown with chrony read. With the faster twist it was a joke and a waste of money on a barrel at any yardage! . The 1in20 seems shoot all the cheap stuff great and the good stuff better! WHY? P.S tell Norm about the larger lead that will fit in Lloyds mod clip, COOL!!!. I thought the max was 65-68. now we need to send a single shot tray to him to lay in some logs!!!!! Giant Grin

lorraine · Member

Ok back to the valve stuff! Don made his valves for modded 2260 tubes and thats why we need a .108 spacer installed by gauge block to work with a discovery that has a reg installed in it. The powerhouse valve is shorter than the disco valve cause it was still in work and almost done and just before the release of the discovery in 2008!. Pretty much all of our cool pcp stuff has alot of DNA with the simple , tried, true, reborn, 2260!!!!!. The build parts on everything tell the story on how these valves fit into there home!

rsterne · Moderator

Most big bores end up with twist rates that are wayyyyyyyyyy too fast.... Twist rates is measured in calibers and then converted to inches, so a .44 cal needs twice as long a twist than a .22 cal when shooting bullets of the same proportions.... I would get the longest twist you can from TJ's (24" I think).... I designed a .357 barrel for TJ's that is a 26" twist, and it works up to about 158 gr.... so you do the math....

If you go to the NOE Moulds site and look through my BBT's, they each have a recommended twist rate.... check out the .40 cals and see how long they are, you will be surprised....

Bullet weight is half the FPE at 950 fps.... So if you want that velocity, take your expected FPE and divide by 2 to get the bullet weight....

Bob