Proud new owner of a 25 Mrod (video uploaded)

[shorty]

What a surprise. Birthday gift + fathers day gift. It's so beautiful it would be a shame to tear it apart before even shooting it. That wife of mine  .

Not even sure what to do with it 

On the 25 platform, how about you guys give me some goals/challenges using all the stock parts (except hammer spring).

Quite - db goal and power level
Power - What FPE and grain size (stock barrel) goal
Accuracy - I can only do up to 25 at the house and 50 at in-laws- </=.5 CTC
Shot count - at what power level and grain weight

We all know what stock levels are so that's gonna get skipped. Who knows, it would be nice to video all the machining and work as a tutorial. I need ideas here before the darkside takes over 

[oldpro]

 Congratz my friend! Best question is What are you going to be using it for that will determine how to go about the build process.

[FuzzyGrub]

Shorty,

I have had a Gen II 25 cal since they first came available.  I tuned it to 860-870-860 w/JSB Kings (25g) for 16 shots, on 3k fill.  So, would be interested in what your spring could do at same power level (42 FPE) and Es.  I have seen some SSGs get about 24 shots at that power, but Es was higher. 

[Airgun.Sniper]

 I have a gen I .25 cal ES is like 15-20fps and Im getting 24 shots at 47 fpe with ssg and 34 grain pellets

[shorty]

Travis,
That stuff doesn't matter what I want to do with it. I will never do 100 yard P-dog hunting on the range, or take 100 lb hogs at 50 yards.

When I did my .22 conversion to .357 there was absolutely no reason for it besides (that's cool).

With that being said, I still have not forgot about you and the 40 FPE super quite, and I still have not forgot about canniborrowsomammo's 98fpe 25.

Somethings gonna give and I need the challenge. Heck, I am bored and my lathe is not getting a work out.

Let me have it 

[shorty]

Fuzzygrub,
Check out acflyers post. He is one of the guys that put the spring in a stock gun. I am pretty sure he did 890 with 25.39's for 20 or 24 shots with a super low ES <2.8%.

If your reading aceflyer, please post since I can not find the numbers.

[shorty]

I am almost tempted to drop that .25 upper onto my modded .22 with regulator.

Boy that would be fun at 35 to 40 fpe for 70 shots on regulation  .

I don't even have pellets yet  .

[aceflier]

Congrats on the .25! You gonna love it! I'm sure you can hit 70fpe. I haven't tested mine since I lubed the hammer with graphite powder. I buggered up the TP in the process so I need more lol.

Here's my stock .25 string with your spring





Here it is after your modded stock valve and poppit spring.

[Airgun.Sniper]

your goal is 70fpe? Well i did a 5 shot string average was about 1005 fps with 33.95 grain pellets. That means 75 fpe.

[aceflier]

your goal is 70fpe? Well i did a 5 shot string average was about 1005 fps with 33.95 grain pellets. That means 75 fpe.

On a stock .25? I've never heard of that before. If so I think your Chrony needs calibrated.

[Airgun.Sniper]

 far as i know it stock...i tossed in an ssg. what would you say if it shot 1000fps on more then one chrony.


 

[Old Corps]

Another new .25 Marauder owner here, love it! Half inch groups @ 40 yards all day long. Since I've only got a 3K scuba tank & hand pump for fills I adjusted the power down to about 775 fps over 16 shots--filling to 2650 down to 1950. JSB 15.4s. Of course now I'm toying with idea of a WAR SSG. I'm ok with the power I'd just like to increase shot count per fill.

Ed

[Old Corps]

far as i know it stock...i tossed in an ssg. what would you say if it shot 1000fps on more then one chrony.


 

I'd say let me borrow one of them there chronies.   Just funnin'.

Ed

[Dairyboy]

75fpe with an SSG even...I'm thinking the gun has been worked on a bit by the previous owner.

[shorty]

Tried to do a little work on the 25 today.

Valve:
Had to run a tap in the 4-40's. Something definitely wrong when I was loosening them.
Hogged to .5"
Throat to .25"
Exit port to .196"
Cap opened to .466"
Dual dimension poppet spring
VAS - JB welded with set screw.

Not sure how the valve is going to work out. I buggered up the raised lip seal for the poppet. Buggered is a light term. I destroyed it with the 1/2" bit. There is no longer a "normal" raised lip for the seal. I did the best I can for as a repair but I am nervous as heck if it's not only gonna hold air but not blow out with the first shot.

Lesson learned, do not use electrical tape to mark the depth of your bit when drilling. Duh....

Hammer:
Counter sunk HT flush with face of hammer.

Hammer spring:
2.1" dual wire spring

Pellets order:
43 eujins and H&N 27 grain. They will be here on Friday. 

Not sure what's gonna go on tomorrow. All  depends on if the gun holds air. Funny thing was, the poppet sealed instantly using a hand pump and has been at 1500 psi for 2 hrs. I just bumped it to 2000 psi to sit overnight.

I am kind of really nervous about destroying the raised seat. Not sure what to expect. A leak would be Ok and expected but, popping off the first shot and losing all the air in one shot makes me nervous.
On the other hand, if it does work out, that small taper towards the throat without a lip seal should really allow the air to flow at low pressures.

Well,
I can't stop thinking about how to due to retractable bolt probe. I really want to run something like that on this gun. I truly like the J-slot but do not have access to a mill.
I have been considering making a drop in retractable bolt. Stupid CAD crashed so I can't share the concept drawing. It would be just a short bolt with a through hole where a piece of drill rod (.093" left over from other project) can pass through. On the probe side, a new probe would be connected to the drill rod and the bolt handle side would have a push stop. In between the push stop and the bolt handle would be a small spring.
So, it cocks as normal but, when you send the bolt forward, you lock the bolt as usual and then push your thumb on the push stop connected to the drill rod. This pushes the pellet past the TP. Remove your thumb and the spring retracts the probe behind the TP.

Sounds a heck of alot easier doing the J-slot. Although, a drop in retractable bolt would be a nice aftermarket product to purchase.

Say,
Where do I get pellets or 25 cal ammo that's heavier than the 43 eujins and shoot well from a stock barrel? 

[tnt76]

Shorty, I'm half way through machining my retractable probe bolt also.  It's still chucked up in the lathe, I should be finished tomorrow, so i'll put pics up. sounds like a similar concept with spring inside.

[shorty]

Definitely would like to see what you have going on.

I have a feeling that this is one of the biggest improvements that can be done to get any kind of high flow valve perform.

[aceflier]

It would be nice not to have the probe in the pellet chamber. May add 30-50fps. It would be awesome if it would be tied into the safety from the factory somehow. Dreaming I guess.

[tnt76]

Definitely would like to see what you have going on.

I have a feeling that this is one of the biggest improvements that can be done to get any kind of high flow valve perform.

I've already seen a gain from 850/860 to 890/900 by retracting the factory bolt back around .150". That was with 54 gr bullets in .257. Will I see another big gain? Not sure

[dippingriz]

If you have the wood stock I would recommend bedding the action and adding a pillar for mounting tension (if you are handy with tools).  I had a really nice 880 AVG fps @ 16 shots with all stock parts before I went with a SSG. 

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