Playing with My extreme as well. 40cal with pics

[bownut]

just wanted to share what I have done with mine I like high power as I hunt so I opted this rout.  Ok so I bought a 40 cal extreme a while back and love the power but was hoping to get more shots so I built a few parts one part is to control air usage and the other is an RPA.  everything else is still stock spring and all.  no valve or transfer port mods at all.  I wanted a lot of shots with lots of power and the rpa lets me go to the range on low power for 6 consistent shots or power it up for a first heavy shot for hunting.  The best it has done is 440 fpe with a 230gr hp since my mods.  only 20fpe below the way it came stock and the rest of the results are below.  I would be interested to know how efficient this mod is?  Also I added a de-pinger an I get no ping at all. just a blast no vibration sounds after that

 4500 psi start pressure 1.5 turns on the power adjuster 230gr hp

 1. 818fps end pressure 4375 341fpe
 2. 876fps end pressure 4125 392fpe
 3. 896fps end pressure 3750 410fpe
 4. 877fps end pressure 3400 393fpe
 5. 849fps end pressure 3125 368fpe
 6. 822fps end pressure 2875 345fpe

 2 turns on the power adjuster with 230gr hp this only gave me a good spread for 4 shots but 2 some what close follow ups also with 4500psi

 1. 866fps 4300 end pressure 383fpe
 2. 909fps 4000 end pressure 422fpe
 3. 897fps 3625 end pressure 411fpe
 4. 870fps 3300 end pressure 386fpe
 5. 836fps 3025 end pressure 357fpe
 6. 813fps 2750 end pressure 337fpe

obviously there is only 4 good shots with 2 rotations on the RPA so 1.5 I think I will stick with.  5 and 6 I really don't count for this string but it was part of my test so I included.

 And the long string of 15 shots with 182gr spitzer with RPA set on full power and 4500psi start pressure

 1. 1018fps 4200 end pressure
 2. 990fps 3900 end pressure
 3. 964fps 3600 end pressure
 4. 923fps 3300 end pressure
 5. 905fps 3000 end pressure
 6. 885fps 2800 end pressure
 7. 854fps 2600 end pressure
 8. 828fps 2400 end pressure
 9. 811fps 2250 end pressure
 10. 791fps 2100 end pressure
 11. 768fps 2000 end pressure
 12. 740fps 1900 end pressure
 13. 720fps 1800 end pressure
 14. 704fps 1700 end pressure
 15. 686fps 1600 end pressure

 and obviously many more shots

[CarsonRatSniper]

What an absolutely beautiful rifle!

I might have to mull over getting one of those..............

[bownut]

Thanks I love it.  As they come they are very powerful excellent rifles and very accurate.  I will have not problem double lunging a deer at 150 yards with this bad boy.  It is my fav at the moment.  It is a one shot wonder the way it comes with a drastically descending shot string just so you know but I made to parts that make it a dream to shoot.  The part that controls air use is the most simplest of parts and takes about 30ming to make and 10 min or less to replace the factory part with.  I am getting over 20 shots before I start getting scared the slug will get stuck I thin shot 20 is still over 500fps I think in the mid 5's when I first made the mod I was getting 36 shots before it got down or just below 500fps but I redesigned for less shots more power. then came the rpa took a stock modification but I don't mind this is a hunting machine now go to the range and back her out for a long consistent string and turn her in for bone crushing power lol.  I am interested to see how my mods work out with the formulas I have seen her for efficiency.  that bob works up.  there is room to tweak what I have done even though I don't think I want to would be interesting to see how far I can take it.  I highly suggest these rifles to anyone.  the 40 cal is awesome for penetrations not to large a diameter and getting awesome velocity flat trajectory's just a great big bore caliber.  Full power penetrates a 4x4 and 2x8 back to back with my spitzers.

[bownut]

I think I figured this out.  so the inside diameter of the tune is in fact 1inch and inside of tube is only about 21.5 inches long with a depinger installed I am guessing now that this is an 18ci tube.  so based off my first string I am getting 1.11558fpe/ci?  is that possible?  or I should say did I possibly do this right.  I do not know if 18ci is accurate but the tube is 24 inches and the 2 valves at each end take up some of that length and so does the depenger that is 2 3/4 inches long with an od of 1.02 ID of .75 and a .15 wall on one end with a .3333 hole drilled through that wall for airflow and and o ring at each end.  no sure how much volume loss that is.

[rsterne]

The easiest way is to calculate the volume of the tube without the depinger and then add the inside volume of it.... If the tube is 1.02" ID and 21.5 - 2.75 = 18.75" long, that is 15.3 CI.... plus the inside of the depinger which is .75" ID x 2.75" long = 1.2 CI.... for a total of 16.5 CI.... Your first string is 2249 FPE total, your second string is 2296 FPE.... The pressure drop in the first string is 4500 - 2875 =  1625 psi / 14.5 = 116 bar x 16.5 CI = 1914 CI total.... For the second string, 4500 - 2750 = 1750 / 14.5 = 121 x 16.5 = 1991 CI total.... Efficiency on string 1 is 2249 / 1914 = 1.18 FPE/CI, and on string 2 is 2296 / 1991 = 1.15 FPE/CI....

Both those strings have 4 shots within a 5% ES, which shouldn't cause more than about 1/2" vertical POI change at 50 yards....

Bob

[bownut]

thanks bob well I did some more modification to my air flow mod to get my high power setting on the RPA a little more powerful took some efficiency away but on high power for a single shot for hunting I am getting 938fps with a 230gr hp.  for 447.54 fpe messed up my strings a bit but here is my new results.

182gr spitzer

4500psi start

1.871.3fps end pressure 4200psi

2.941.5fps end pressure 3975psi

3.961.2fps end pressure 3600psi

4.940.5fps end pressure 3300psi

5.908.2fps end pressure 3000psi

6.881.3fps end pressure 2750psi

so that is a total of 1750 psi use with a total fpe of 2043.57.  So 1750 psi = 120.66 bar.  so with the ci being 16.5 I get 120.6x16.5=1989.9.  so then I take that and do 2043.57/1989.9=1.027  so that gives me an efficiency of 1.027/ci ?  I think with some power adjust playing it might do better not sure but I think I like that with a hi power fpe of 447.54.  I guess with the 230's my efficiency would go up as well.  so how do I calculate bullet efficiency?  from my number to psi use on high power the 230's are most efficient with my 182 spitzers coming in a close second. that would be air use to fpe also but what is the real way to do it for a given bullet. I have no technical data on that. 

[rsterne]

You can't calculate how the efficiency changes when you change bullets, you have to measure it.... but generally heavier bullets are a bit more efficient.... I don't know what range you hunt at, or how small a group you require, but I would stick with about a 5% ES for over 50 yards, unless your groups say otherwise.... That means with a 961 fps high, you throw out all the shots under 913 fps, which only leaves you with 3 good shots.... All 6 shots are within a 10% ES, and for your purposes you may find that OK....

Bob

[bownut]

Rsterne you have all the answeres lol

well that is for target fun with the power adjuster on low power.  If I sit in the deer stand I am going to want my first shot to be most powerful so I will have the power adjuster all the way in.  I think with 938fps and 447.54 fpe I will shoot to 150 yards.  I have taken deer over 100 yards with a Samyang 909 untuned so I think this gun will do it.  it is very accurate compared to that 909s I probably should not have take a close to 120 yard shot but I know how the gun shot at that range and I was prone with a bipod and knew I could do it.  so given the perfect situation with a good rest I would sling one to 150 yards.  I am not worried about consistent shots when hunting because only on the very rare occasion do I need more than one.  and my second on full power is still just over 900fps so not to worried about that.  Mostly where I hunt it is wood and a lot of my spots are pretty thick and I don't get shots over 50 yards any way but occasionally I will hunt a small clear cut and a long strip food plot (planted road where I get offered up to 175 yard shots.  I think I will cut it off at 150 though.  based of my experience with this gun at 100 yards a double lung on a deer with a good rest will be easy with this gun.  but I will test that on paper first of course.  I plan to do some 150 200 and 300 yard plinking soon so we will see where my comfort level moves to after that.  I will have it dialed in for 100 yards and just aim mid heart at 50 and so on.  that is what I did with the 909.  as you can see what I have done to this gun the more you pull the trigger off of one fill the less air it uses I get over 20 shots I am kinda amazed.  There can be a lot more done to these guns with out changing the transfer port valve stem or valve at all than just simply putting a light spring in it.  I make a part that almost any one can install them selves and modify according to there needs to control how much air is used per shot.  I love this thing probably the most tunable gun I have ever seen with very little work needed.

[rsterne]

I would recommend that you find a tune that will give you at least TWO shots of nearly equal velocity for your hunting tune.... If you go for a declining shot string, your efficiency will be HALF or less of what you have now.... My DAQ .308 Exile, as delivered shot 836, 786, 742, and the efficiency was only 0.38 FPE/CI.... By dropping the preload, it shoots 826, 833, 832, 824, 811, 792 on less air than before, at 0.88 FPE/CI.... My 6th shot is now faster than the 2nd shot in stock tune.... and the maximum velocity only dropped 3 fps....

Bob

[bownut]

those are some sweet numbers.  I could probably keep playing with it and get a closer string for sure but it would be at the cost of power I would assume since I don't not want to touch the valve.  my main goal was to get as little power lose as possible over the factory set up but get a lot more shots and I ended up with a pretty good string to work with as well.  I guess if I set it on low power and filled to 4200 I would get 3 shots with only a 20fps deviation but really my first shot is all that matters in the woods.  I don't go out planning on killing 6 deer lol just one a hunt is good enough for me.  and the more power the better the hollow point works I guess I my though on it.  not 100% sure just how far this gun would go with some more mods closing up the transfer port a bit would tighten up that string just don't really want to go there.  for my needs I prefer my first shot to be as powerful as possible for hunting with a gun that is still target fun.  But I see what you mean with that string it really does not matter the power difference is negligible.  I have been try to get on Dennis's list for years with no luck.  It makes me mad when I see people get on it and then shortly after they have a brand new DAQ for sale in the classifieds they did not even want the gun they just wanted to buy it for 600 or 700 and sell it for 1000 and nocks guys like me out that actually want the gun I would be getting.

[rsterne]

With your gun, I would tune for two equal shots starting at 4500 psi, and then you would have a good solid backup on top of that.... I think you would find the difference between that and cranked to the max would be REALLY minimal, certainly the deer wouldn't even know the difference.... and I'm betting your 3rd shot would be faster than your 2nd with a flat-out tune....

Bob

[bownut]

yea I think the tune is good where its at I might be able to achieve what you are suggesting with simply playing with fill pressures and the RPA.  I have tried it on half power at 4500 and it still descends but the well let me look.  ok the deviation I took in my notes from shot one to two was only 12fps and then another 20fps from shot two to three.  so that is pretty good I still got 427 fpe on the top end.  not to bad I guess and I see your point I don't think the deer will care about 20fpe when we are talking about these powers.  What is suggested for lung shots on hogs in means of FPE we have them upwards of 400 pounds where I hunt most in the 150 to 250 range and the occasional beast.   I have never shot one with an airgun.  I have shot deer coyote squirrel a turkey and some other small critters you think full 400fpe + will take one of the big ones.  some one told me you need 400fpe.  I just don't see that as I have gotten pass through shots on deer with 250fpe in a 45 slug and one deer weighed 220lbs.

[Fur-n-dirt]

just wanted to share what I have done with mine I like high power as I hunt so I opted this rout.  Ok so I bought a 40 cal extreme a while back and love the power but was hoping to get more shots so I built a few parts one part is to control air usage and the other is an RPA.  everything else is still stock spring and all.  no valve or transfer port mods at all.  I wanted a lot of shots with lots of power and the rpa lets me go to the range on low power for 6 consistent shots or power it up for a first heavy shot for hunting.  The best it has done is 440 fpe with a 230gr hp since my mods.  only 20fpe below the way it came stock and the rest of the results are below.  I would be interested to know how efficient this mod is?  Also I added a de-pinger an I get no ping at all. just a blast no vibration sounds after that

 4500 psi start pressure 1.5 turns on the power adjuster 230gr hp

 1. 818fps end pressure 4375 341fpe
 2. 876fps end pressure 4125 392fpe
 3. 896fps end pressure 3750 410fpe
 4. 877fps end pressure 3400 393fpe
 5. 849fps end pressure 3125 368fpe
 6. 822fps end pressure 2875 345fpe

 2 turns on the power adjuster with 230gr hp this only gave me a good spread for 4 shots but 2 some what close follow ups also with 4500psi

 1. 866fps 4300 end pressure 383fpe
 2. 909fps 4000 end pressure 422fpe
 3. 897fps 3625 end pressure 411fpe
 4. 870fps 3300 end pressure 386fpe
 5. 836fps 3025 end pressure 357fpe
 6. 813fps 2750 end pressure 337fpe

obviously there is only 4 good shots with 2 rotations on the RPA so 1.5 I think I will stick with.  5 and 6 I really don't count for this string but it was part of my test so I included.

 And the long string of 15 shots with 182gr spitzer with RPA set on full power and 4500psi start pressure

 1. 1018fps 4200 end pressure
 2. 990fps 3900 end pressure
 3. 964fps 3600 end pressure
 4. 923fps 3300 end pressure
 5. 905fps 3000 end pressure
 6. 885fps 2800 end pressure
 7. 854fps 2600 end pressure
 8. 828fps 2400 end pressure
 9. 811fps 2250 end pressure
 10. 791fps 2100 end pressure
 11. 768fps 2000 end pressure
 12. 740fps 1900 end pressure
 13. 720fps 1800 end pressure
 14. 704fps 1700 end pressure
 15. 686fps 1600 end pressure

 and obviously many more shots

Do you have pics of the air control and power adjuster?  Are these off the shelve items or full custom parts.  Looks great.

[bownut]

The pictures in the post show the gun with the RPA I made for it.  I designed and built the parts my self with my lathe and my mill.  I can make the parts again and you can install but to find the perfect balance takes install test un install machining install test and so on.  now that they are built and complete I could get them closer on the first try but all guns are different and would still need tweaking.  going to be working on a few guns for some guys here soon one is in the mail on its way here now a corsair 308 and then later a 500 nitro express extreme.  the more guns I work on the more I will see if machining these to the same dimensions every time will yield nearly the same results every time.   the most important part is the one I use to control air use.  as you can see with each additional shot the gun makes after the top of the curve the less air it uses.  Kinda backwards right?  well that is what every one tells me but it allows for a bell curve and then a ton more shots to spare.  a typical bell curve once it has reached the top of the curve uses more and more air with each additional shot only allowing the gun to have x amount of shots left after the string is gone.  so I liked this way of doing just for all the extra shots or when My string is done I can refill and not have to add as much air as I would doing it the other way. 
you can email me at timberridgearchery@yahoo.com for my number so I can explain better.  this can be done without a RPA but you will only have the low power option and not be able to go from low power to high power at your finger tips.

[Fur-n-dirt]

The pictures in the post show the gun with the RPA I made for it.  I designed and built the parts my self with my lathe and my mill.  I can make the parts again and you can install but to find the perfect balance takes install test un install machining install test and so on.  now that they are built and complete I could get them closer on the first try but all guns are different and would still need tweaking.  going to be working on a few guns for some guys here soon one is in the mail on its way here now a corsair 308 and then later a 500 nitro express extreme.  the more guns I work on the more I will see if machining these to the same dimensions every time will yield nearly the same results every time.   the most important part is the one I use to control air use.  as you can see with each additional shot the gun makes after the top of the curve the less air it uses.  Kinda backwards right?  well that is what every one tells me but it allows for a bell curve and then a ton more shots to spare.  a typical bell curve once it has reached the top of the curve uses more and more air with each additional shot only allowing the gun to have x amount of shots left after the string is gone.  so I liked this way of doing just for all the extra shots or when My string is done I can refill and not have to add as much air as I would doing it the other way. 
you can email me at timberridgearchery@yahoo.com for my number so I can explain better.  this can be done without a RPA but you will only have the low power option and not be able to go from low power to high power at your finger tips.

Very cool..  If I pick up another extreme, I would be interested in talking more..

[Saddlemountain]

The 2 shot tune is good advice, basically at the peak of the curve. Years ago I used to use a 909 single tuned for 200 gr SWC for two shots then the third with a  155 gr EPPUG would have same POI. Dropped three deer in less than a minute, even the EPPUG (third shot) double lung passed through.

[Fur-n-dirt]

The 2 shot tune is good advice, basically at the peak of the curve. Years ago I used to use a 909 single tuned for 200 gr SWC for two shots then the third with a  155 gr EPPUG would have same POI. Dropped three deer in less than a minute, even the EPPUG (third shot) double lung passed through.

Very cool Will

[Tommy]

I am an old disabled man with a little blackhawk that is giving more enjoyment then i thought possible. But the other good part about this hobby is finding this forum and being able to marvel at the genious of the members. I hope this is in the right place but I just had to say thank you
Tommy