My new .25 Mrod!

My new .25 Mrod!

Joined: December 28th, 2010, 5:05 pm

April 13th, 2012, 8:03 am #1


Hey guys! I thought I would share my new Mrod with you all. I haven't done anyting to it as far as tuning but I did do a couple things to it. My pops gave me a .25 Mrod for my birthday and I'm stoked. I was going to build a custom .25cal repeater bolt action rifle based on the Mrod so I started collecting some parts and I ended up putting them on this. I've got some ideas in the works and this thing will be different down the road and of course I'm gonna try to work my magic on the valve to see what I can do with this rifle. Since this has a velocity adjuster on the valve I'm going for a high power build cause I can use that screw to slow it down if needed. 

I had purchased a camo stock from Crosman  a couple of months ago and also purchased a titanium trigger for the Mrod because I was planning to use them on my custom build but they are now on this. I drill some holes in the stock inside by the forearm area and I also took the butt plate off and drill some holes in the butt stock, I still meed to clean it up but you can't see it so I'll do it later. It weighed 3.5 pounds before I drilled and 3 pounds after. The trigger is a little more curved and feels better than the stock one and of course it's a little lighter. I don't know about anyone else but this is the best trigger action I've ever felt on a pellet gun and that was before I installed the new trigger.







I'm left handed and I'm use to right handed bolt actions but being this a repeater and a 10.5 pound rifle w/bipod (getting a new scope that might drop another pound) it's a pain in the butt when you want a follow up shot when holding the rifle. I don't mind using my right hand when I'm loading singles shooting on a bench or using lighter and or better balanced rifles that's easier to hold up with the trigger arm. I went looking for left handed fixies and I saw on another forum where this guy machined a new slot in the breech and air tube and did a couple other things and made it look stock but I didn't want to attempt that yet since I'm still learning how to use my lathe correctly and messing up a breech would suck. I took a simpler route and made a handle out of 7075 aluminum 1" rod. I had to make some clearance so I decided to mill it and I didn't tighten the handle good enough in the vice and it slipped causing the mill to dig in and I couldn't tell at first but once I started sanding it I noticed that I poked a hold in it just under the mounting bolt. I drilled a hold in the end of the bolt and tapped it to accept a 10/32 bolt which is used to mount the new handle.  I'm gonna make another one but for now this one works and it's now the prototype so I didn't finish it up that well and I know what exactly to do next time. It works great but you just got to remember to push up instead of pulling down once closing the bolt to lock it. Also since I had the bolt out I decided to make the air flow channel flow smoother so I took my dremel and a diamond coated ball bit that was a tad bigger than the channel and work on it for maybe a minute or two. I did take some 1500 grit paper to it to make it smoother too. It worked great. I gained 20fps through out the shot count by doing this. Couldn't believe it so I shot 4 more clips through it to make sure and got the same results with all the clips refilling the air chamber to 3000psi after 16shots or two clips. I came across this mod on another forum where this guy smoothed his bolt out and gained 10-12fps through out his shot string. So it thought I would give it a try, didn't think I'd gain 20fps but I did and I'm stoked.











Here's a 16ct shot string after I smoothed the bolt out. Before I smoothed it out it was starting off with 850's then peaking with 863fps and ending within the mid to high 820's after 16 shots. I'm using jsb 25.39 exacts and it's the stock hammer spring and valve velocity settings from the factory. I still haven't touched those.

877.8 - 3000psi
875.3
877.6
873.8
877.2
873.5
877.6
881.9 - 2600psi
877.8
878.9
873.3
872.4
863.6
859.8
853.2
845.3 - 2180psi

The ldc is made with carbon fiber tubing and delrin. I had it laying around cause I don't have any airguns right now that take 1/2"x20 thread on attachments. I also had some delrin pieces laying around that I could use so I machined the delrin to fit the shroud end cap and drilled two holes through the delrin into the endcap to hold it in place with set screws and installed it in place of the 1/2"x20 piece that was in ldc. Worked out pretty good and I've got a new end cap on the way to make it a easier switch. Not only does this thing collect lead dust it also made the rifle more quiet. <img alt="happy.gif" src="/images/happy.gif" width="14" height="14"> The Mrod ping got to me like a lot of other Mrod owners so I made a depinger and installed two pieces of 1-1/4" poly tubing about 5/8" wide that I cut notches along the sides then installed them by folding them instead of cuting them down the middle and overlapping them. Amazing no more ping! I'm making a new shroud for this soon and I'll post pics once I get that done.

Here's pic of the shround end cap installed in the ldc.



This Mrod is gonna end up like my other two crosmans where they're modded out pretty good and far from stock. <img alt="wink.gif" src="/images/wink.gif" width="14" height="14">

That's it for now! Sorry for all the writing!

Dave

 
Last edited by Yellowdman on April 13th, 2012, 8:09 am, edited 1 time in total.
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Joined: March 25th, 2011, 2:35 am

April 13th, 2012, 12:41 pm #2

Assume you are talking about the scalloped portion on the bolt that turns the air and directs it to the rear of the pellet, correct..??

Did you smooth edges along length...??? Trying to be clear what you did.
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Joined: December 28th, 2010, 5:05 pm

April 13th, 2012, 4:00 pm #3


Sorry wasn't sure what to call it since it's not really a "flow through" but more of a flow channel. I didn't take before pics and I should have. When I first pulled the bolt out I didn't see the 90 deg. angles this guy was talking about and it looked fine to me but when you look at the stock one good you'll notice that it's kind of square on the sides. I also noticed the the channel isn't that big or isn't as big as I thought it should be for a .25 cal. I have a through bolt on my 007 build and I drilled it out as big as I could to get as close to the internal size of the pellet skirt and and it made a difference. I thought it couldn't hurt to make this more round and a tad bigger. I have this little dremel diamond tip round bit that fit half way in so I decided to try it. The bit worked perfect. It opened up the channel and made it more rounded on the inside. I took the bolt out so I could get a better pic for you. Only draw back to the diamond bit is that it doesn't leave a smooth finish so you'll need to smooth it out. You'll see in the pic that mine isn't super smooth, gonna pull it out and make it smoother here in a bit.

[/IMG]

[/IMG]

the dark line is a reflection

[/IMG]
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Joined: March 1st, 2002, 12:22 am

April 13th, 2012, 5:01 pm #4


Camo, custom bolt work, Ti triggers......

very creative on the leftie bolt problem.

 


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Joined: December 28th, 2010, 5:05 pm

April 13th, 2012, 5:39 pm #5


I had some friends over shooting it and as I watched them all use their right trigger hand to cycle the bolt I was getting a little jealous seeing they had an easier time with it. I had to do something and I did. <img alt="happy.gif" src="/images/happy.gif" width="14" height="14"> The hardest part about this was drilling the hole into the back of the bolt. The first layer is easy but then you hit part of the handle that is pressed in and it's hardened steel. I used the same diamond dremel bit as above and some others that were flat on top to grind past the hardened part. It took a little bit but I got it!

One thing I noticed before I made and installed the handle was every time I shot my bolt handle would move upperward from the blast of air. I was thinking that my new handle (being that it's in the up position when closed) would put unwanted leverage on the bolt and make it open up more when I took a shot. I decided on using the 7075 aluminum rod for the handle material since it's lite and strong . I also made it a tad bit shorter than the stock handle to help with weight control and placement. I've shot it a bunch since I finished it yesterday and the handle doesn't even move so no leverage problems here! I'm sure the work I did on tip helped some too.
Last edited by Yellowdman on April 18th, 2012, 12:30 am, edited 1 time in total.
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Joined: March 25th, 2011, 2:35 am

April 16th, 2012, 8:29 pm #6

Sorry wasn't sure what to call it since it's not really a "flow through" but more of a flow channel. I didn't take before pics and I should have. When I first pulled the bolt out I didn't see the 90 deg. angles this guy was talking about and it looked fine to me but when you look at the stock one good you'll notice that it's kind of square on the sides. I also noticed the the channel isn't that big or isn't as big as I thought it should be for a .25 cal. I have a through bolt on my 007 build and I drilled it out as big as I could to get as close to the internal size of the pellet skirt and and it made a difference. I thought it couldn't hurt to make this more round and a tad bigger. I have this little dremel diamond tip round bit that fit half way in so I decided to try it. The bit worked perfect. It opened up the channel and made it more rounded on the inside. I took the bolt out so I could get a better pic for you. Only draw back to the diamond bit is that it doesn't leave a smooth finish so you'll need to smooth it out. You'll see in the pic that mine isn't super smooth, gonna pull it out and make it smoother here in a bit.

[/IMG]

[/IMG]

the dark line is a reflection

[/IMG]
I can see clearly what you did.uch appreciated.
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Joined: February 5th, 2003, 4:29 am

April 18th, 2012, 12:51 pm #7

Hey guys! I thought I would share my new Mrod with you all. I haven't done anyting to it as far as tuning but I did do a couple things to it. My pops gave me a .25 Mrod for my birthday and I'm stoked. I was going to build a custom .25cal repeater bolt action rifle based on the Mrod so I started collecting some parts and I ended up putting them on this. I've got some ideas in the works and this thing will be different down the road and of course I'm gonna try to work my magic on the valve to see what I can do with this rifle. Since this has a velocity adjuster on the valve I'm going for a high power build cause I can use that screw to slow it down if needed. 

I had purchased a camo stock from Crosman  a couple of months ago and also purchased a titanium trigger for the Mrod because I was planning to use them on my custom build but they are now on this. I drill some holes in the stock inside by the forearm area and I also took the butt plate off and drill some holes in the butt stock, I still meed to clean it up but you can't see it so I'll do it later. It weighed 3.5 pounds before I drilled and 3 pounds after. The trigger is a little more curved and feels better than the stock one and of course it's a little lighter. I don't know about anyone else but this is the best trigger action I've ever felt on a pellet gun and that was before I installed the new trigger.







I'm left handed and I'm use to right handed bolt actions but being this a repeater and a 10.5 pound rifle w/bipod (getting a new scope that might drop another pound) it's a pain in the butt when you want a follow up shot when holding the rifle. I don't mind using my right hand when I'm loading singles shooting on a bench or using lighter and or better balanced rifles that's easier to hold up with the trigger arm. I went looking for left handed fixies and I saw on another forum where this guy machined a new slot in the breech and air tube and did a couple other things and made it look stock but I didn't want to attempt that yet since I'm still learning how to use my lathe correctly and messing up a breech would suck. I took a simpler route and made a handle out of 7075 aluminum 1" rod. I had to make some clearance so I decided to mill it and I didn't tighten the handle good enough in the vice and it slipped causing the mill to dig in and I couldn't tell at first but once I started sanding it I noticed that I poked a hold in it just under the mounting bolt. I drilled a hold in the end of the bolt and tapped it to accept a 10/32 bolt which is used to mount the new handle.  I'm gonna make another one but for now this one works and it's now the prototype so I didn't finish it up that well and I know what exactly to do next time. It works great but you just got to remember to push up instead of pulling down once closing the bolt to lock it. Also since I had the bolt out I decided to make the air flow channel flow smoother so I took my dremel and a diamond coated ball bit that was a tad bigger than the channel and work on it for maybe a minute or two. I did take some 1500 grit paper to it to make it smoother too. It worked great. I gained 20fps through out the shot count by doing this. Couldn't believe it so I shot 4 more clips through it to make sure and got the same results with all the clips refilling the air chamber to 3000psi after 16shots or two clips. I came across this mod on another forum where this guy smoothed his bolt out and gained 10-12fps through out his shot string. So it thought I would give it a try, didn't think I'd gain 20fps but I did and I'm stoked.











Here's a 16ct shot string after I smoothed the bolt out. Before I smoothed it out it was starting off with 850's then peaking with 863fps and ending within the mid to high 820's after 16 shots. I'm using jsb 25.39 exacts and it's the stock hammer spring and valve velocity settings from the factory. I still haven't touched those.

877.8 - 3000psi
875.3
877.6
873.8
877.2
873.5
877.6
881.9 - 2600psi
877.8
878.9
873.3
872.4
863.6
859.8
853.2
845.3 - 2180psi

The ldc is made with carbon fiber tubing and delrin. I had it laying around cause I don't have any airguns right now that take 1/2"x20 thread on attachments. I also had some delrin pieces laying around that I could use so I machined the delrin to fit the shroud end cap and drilled two holes through the delrin into the endcap to hold it in place with set screws and installed it in place of the 1/2"x20 piece that was in ldc. Worked out pretty good and I've got a new end cap on the way to make it a easier switch. Not only does this thing collect lead dust it also made the rifle more quiet. <img alt="happy.gif" src="/images/happy.gif" width="14" height="14"> The Mrod ping got to me like a lot of other Mrod owners so I made a depinger and installed two pieces of 1-1/4" poly tubing about 5/8" wide that I cut notches along the sides then installed them by folding them instead of cuting them down the middle and overlapping them. Amazing no more ping! I'm making a new shroud for this soon and I'll post pics once I get that done.

Here's pic of the shround end cap installed in the ldc.



This Mrod is gonna end up like my other two crosmans where they're modded out pretty good and far from stock. <img alt="wink.gif" src="/images/wink.gif" width="14" height="14">

That's it for now! Sorry for all the writing!

Dave

 
When they dip stocks in vinyl covering? Theres a certain name for it.

ernie
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Joined: December 28th, 2010, 5:05 pm

April 18th, 2012, 7:13 pm #8


or Hydrographic Printing are the correct terms I believe.

 

Dave
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