Most Compact Marauader!

[ackuric]

I agree with your comments about it.  I think if you had a wider piece it would allow you to do more rounding/contouring and you may like it more.  Idk, you may be able to add a couple of elbows and extend the assembly more forward and then you could really do more contoured shapes and reduce the sharp angle more.  Just trying to throw in my crazy thoughts on it as usual.

I am going for function over aesthetics. The hand guard is just there right where the balance of the rifle is and for proper grip. This rifle certainly isn't being made with cosmetics coming first. I have bigger pieces of kydex I can use but I cut the kydex down to its current size because I wanted it to be minimal, although I may always choose to tinker with another version and could have multiple snap on stocks, in fact I likely will!

So far this version I am 100% happy with, the feel is great and it feels sturdier than the OEM stock


I spent a good amount of time worrying about attaching a hand guard and having designed a snap on style that has zero movement makes me sleep well tonight!

-Matt

[ackuric]

Test filled rifle to 2300 psi (low on air) and letting it sit over night. I started on a new hand guard/stock that will hopefully be more appealing to the eye and blend with the rifle more.  Taking Keith's advice and trying one a bit bigger. Hopefully I knock that out in the couple days. I really think the new stock design will be a keeper, even though the current one has grown on me and feels great. I'll be able to design as many as I want really and snap them on / off within seconds.

-Matt

[Privateer]

I like the extra plenum.
Here's just a thought I had looking at the lines of the gun.
What if the gauge was on the end of the extra plenum facing towards the muzzle.
It would still be functional but allow a lower profile cover to be designed.

[ackuric]

I like the extra plenum.
Here's just a thought I had looking at the lines of the gun.
What if the gauge was on the end of the extra plenum facing towards the muzzle.
It would still be functional but allow a lower profile cover to be designed.

I've thought about that but I can't safely drill/tap the gauge into the end of the plenum, at least not imo. What I could do it have maybe the gauge come out the side which would allow a lower profile. I just can't find a 3 way 1/8 npt connection that does what I want, only tee's that have one of the connections going downwards instead of sideways.

-Matt

[Privateer]

Where did you get the plenum? I could use something like that myself.

[ackuric]

Where did you get the plenum? I could use something like that myself.

Ebay. I used a 20 gram co2 cartridge that provides 25 cc more plenum space. It uses a 3/8 to 1/8 npt adapter fed off a tee that comes off the gauge block/plenum. Its basically like Lloyds double tube concept but for regulated rifles. I would love a 80-100 cc "double tube" made out of aluminum where the gauge then sticks in front of it like suggested but that would cost a few pretty pennies.

-Matt

[ackuric]

Welp the good news is in. Rifle held every bit of air over the course of about 20 hours! I am slacking a little bit on my new stock design but I am kind of mulling it over in my head before executing it. I have the shell shaped @ 12 inches in length and will likely use 10-11" of that. I will likely keep the same overall idea down just extend it up front and try to make it flow with the pistol grip out back.

-Matt

[ackuric]

Version two of the handguard/stock. Not 100% complete. Rifles assembled weight WITH air is currently 4.8 lbs!



-Matt

[Xraycer]

Version two of the handguard/stock. Not 100% complete. Rifles assembled weight WITH air is currently 4.8 lbs!



-Matt

Ok, I like this version better. Nice job!

[ackuric]

Version two of the handguard/stock. Not 100% complete. Rifles assembled weight WITH air is currently 4.8 lbs!



-Matt

Ok, I like this version better. Nice job!

Thanks, me too! I took Keith's advice and think it turned out well. I got 4 sheets of 12"x8" kydex for around 10-12$ so I could mock up several stock designs over the course of time! They also make cool infused kydex. Was thinking of ordering a sheet like this and making a stock out of it.



We'll see!

-Matt

[Xraycer]

Was thinking of ordering a sheet like this and making a stock out of it.



We'll see!

-Matt

I've got the matching baseball hat, from Dick's last month

[Privateer]

Where did you get the plenum? I could use something like that myself.

Ebay. I used a 20 gram co2 cartridge that provides 25 cc more plenum space. It uses a 3/8 to 1/8 npt adapter fed off a tee that comes off the gauge block/plenum. Its basically like Lloyds double tube concept but for regulated rifles. I would love a 80-100 cc "double tube" made out of aluminum where the gauge then sticks in front of it like suggested but that would cost a few pretty pennies.

-Matt

Well you do have me looking at the idea. Thanks.
I may pick up a Daisy Avanti 888 CO2 cartridge and modify that.
Found them for $19.95 plus shipping.

[ackuric]

Where did you get the plenum? I could use something like that myself.

Ebay. I used a 20 gram co2 cartridge that provides 25 cc more plenum space. It uses a 3/8 to 1/8 npt adapter fed off a tee that comes off the gauge block/plenum. Its basically like Lloyds double tube concept but for regulated rifles. I would love a 80-100 cc "double tube" made out of aluminum where the gauge then sticks in front of it like suggested but that would cost a few pretty pennies.

-Matt

I use the threaded co2 cartridge, 16-20 gram cartridges fit just fine in the original stock.

Well you do have me looking at the idea. Thanks.
I may pick up a Daisy Avanti 888 CO2 cartridge and modify that.
Found them for $19.95 plus shipping.

http://www.ebay.com/itm/Genuine-Innovations-20gram-Threaded-CO2-Cartridges-2-Pack-/182707430260?epid=1000024608&hash=item2a8a362374:g:auwAAOSwLKpZiK9k

This is what I used. 19.80$ and free shipping.

-Matt

[Privateer]

[triggertreat]

Yes, that forearm does look better, but it's all your hard work that makes it so.  Nice job and you have room to expand the plenum even more if you want to.

[ackuric]

Not sure how that will do with HPA and what kind of connection is that? I used the threaded co2 cartridges. The ones I use are definitely good enough for HPA.

[ackuric]

Yes, that forearm does look better, but it's all your hard work that makes it so.  Nice job and you have room to expand the plenum even more if you want to.

Thanks, I certainly could go with a bigger plenum! I've tossed around the idea of a 33 or a 42 gr co2 cartridge which would allow me to make 65-70 FPE but IMO 60 FPE is plenty for a regulated .25 cal! Unregulated this rifle would easily push 80+ FPE.

If I wanted gobs of power, I would make a slightly longer tube from titanium for 4,500 psi fills, regulate it at 2500 with 80-100 cc's of plenum, and call it good! 

-Matt

[Privateer]

Not sure how that will do with HPA and what kind of connection is that? I used the threaded co2 cartridges. The ones I use are definitely good enough for HPA.

Not sure to be honest what it will do with HPA. The connections at each end would allow other fittings to be fabricated for my needs. I could also go with a tube from Hatsan. Kind of expensive but I know the rating on them.
The AT44 short tube is 180CC. The one for the Hatsan Pistol is 50CC. Both can take 2900PSI+
I do have an extra 180CC tube here.

[ackuric]

So I put a little trigger time in over the weekend. A few notes on this build so far...Prod trigger group has a LOT of drag sear, I immediately noticed a difference in my FPS using the same hammer / spring combo, easily a good 100 fps lost when compared to the mrod trigger group. I did a lot of custom work on my valve to reduce the requirement of hammer weight/spring rate and this kind of sets it back a bit...I don't think I will sleep well until I fix it somehow! I tried a really light sear spring but it's a bit too light and doesn't push the sear up during cocking, so I'll have to keep trying. I also removed material from the grip frame to allow it to sit more flush with the mrod tube, which likely makes the modified/taller sear sit a bit higher than normal in my build, I don't think it adversely effects the fps anymore than one that wasn't modified would though.

Prod trigger itself is of good quality, but next to a really fine tuned marauder trigger its no match. Stage 1 in very light, but stage 2 seems a little on the stiff side when compared to a marauder trigger set at a medium-light setting.

The rifle feels amazing to hold. The length of pull can be adjusted to perfectly suit your shooting position, being able to adjust that on the fly is invaluable imo! I use a lot more length of pull when I shoot prone than when I off hand.

I have a lot of modifications done which include a leather faced striker that help reduce shot noise. Being that the stock is attached to the end cap, and is metal compared to the oems plastic, a little metallic noise travels down the rods but I feel in time I will either remedy it or live with it as its minimal and not a huge down side. I think its mostly my ssg bolt coming back and smacking the adjuster on return, but for those with regular metal/plastic striker faces it would likely be more pronounced...I may try a set of delrin rods for the stock but I certainly feel those will flex some, probably just need a damper on my ssg bolt/adjuster...quite a few ways to skin this cat

My custom stock isn't complete but was good enough for some trigger time, and it feels great and does its job well!

I tried out some 19.91gr from H&N...and found that my gen ll modified bolt is turned down too much for these pellets, they were sticking half way into the barrel port, their so light weight that they remove a ton of material from the back of the pellet, its hollowed out very deep. I swapped my gen l bolt in which pushes them all the way by the OD of the skirt instead, and to my surprise my fps went down around 50 instead of up! Could of been a fluke but I just scratched my head and gave it more spring pre-load till I got fps back up.

Maybe having a pellet stick half way in the port is a good thing for fps, possibly more pressure build up prior to pellet really moving? Either way accuracy seemed to suffer a tad so I am not sure it's a fruitful thing to chase after, and very well could have been some fluke for me!

-Matt

[ackuric]

So I found a partial solution to my problem with the taller sear and my sanded down grip frame. I added a .015" gasket in between the tube and the grip frame to allow the .032" taller sear to not seat as deeply. I gained about 30 fps and my es tightened up considerably where as before it was a bit erratic.

The next still will be finding a slightly lighter sear spring to replace the stock one.

As soon as the SS Valve from A.R.T is available I'll be jumping on the opportunity to try one out. I currently have around 45 cc's of plenum and with the new valve I would likely see a few more cc's which would mean more power on tap!

-Matt