CRAZY SHOT STRING....???? GET ALOAD OF THIS.

[bmazz007]

MROD 25 CAL 10 SPRING BARRACUDAS 31.02 GR 16 SHOTS WHY???

FIRST OF ALL THIS CAN ONLY HAPPEN TO ME.  25 MROD TRYING TO TUNE IT. iTS ABOUT TO FIND A NEW HOME OVER 400 SHOTS AND I STILL CANT GET IT ..



PORT VALVE 4.0
PRELOAD 6.0                        31.02 GRN
STROKE 5/8

STARTING PSI 3050

1   829    PSI 3050
2   835
3   839
4   896    PSI 2800
5   861
6   810       2650
7   789
8   874
9   777      2300
10 779
11 767
12 813      2000
13 822
14 791
15 712      1700
16 697      1600


Sorry for the caps..

Test 2

valve 3.5
preload 5.0
stroke 1 3/4

1 781 - 3050
2 784
3 837
4 838
5 787
6 786  2650
7 783
8 843  2550
9 770
10 818 2400
11 743
12 747 2250
13 729
14 780  2100
15 754
16 711  2000
17 751  1950
18 700
19 681  1800

Is this getting better???
 

[ezman604]

I know you're upset, but please don't shout at me. 
Well, it's fun to play and learn. IF you decide it needs a new home, let me know. I may be in the market for another experimental MRod...or to have a spare parts gun.
LOL
Keep at it, I'm sure you'll stumble onto a winning combo using the tricks posted here on GTA.
SAFE & Happy Shooting!!!!
Dave
 

[bmazz007]

I know you're upset, but please don't shout at me. 
Well, it's fun to play and learn. IF you decide it needs a new home, let me know. I may be in the market for another experimental MRod...or to have a spare parts gun.
LOL
Keep at it, I'm sure you'll stumble onto a winning combo using the tricks posted here on GTA.
SAFE & Happy Shooting!!!!
Dave
 

Thank you sorry for the caps lock I am just frustrated. going through air and pellets like water.

Bill

[ezman604]

LOL
ALL of us that play with the internals of an airgun get frustrated at times. It's all part of the experience and the learning cycle. Just hang in there. Or send me a pm for my mailing address.
HeeHee

[Macky]

I don't own a M-Rod, but is it typical to see a double bell curve in the shot sting?  My P-rod didn't do that and I've done extensive test this last week. 500 pellets worth. Just a guess, but would the higher pressure/more air volume cause an air leak in the breech seal? 

[CitySniper]

How is your chrony setup?....indoor/outdoor, what kind of lights? .... Best you shoot about 1 foot away and 6-8 inches about the sensors

You have not mentioned how the gun is actually shooting as far as accuracy...

[rsterne]

I would recommend about 3 feet from the first sensor.... any closer and you may be getting false readings....

Bob

[bmazz007]

How is your chrony setup?....indoor/outdoor, what kind of lights? .... Best you shoot about 1 foot away and 6-8 inches about the sensors

You have not mentioned how the gun is actually shooting as far as accuracy...

The gun shoots accurate .. I have been testing with crony inside under lights with the pucks I am about 7- 8  inches away. I am trying to achieve a somewhat consistent shot string using trying to get at least 16 shots fairly close in FPS and be somewhere in the mid to lower 840 830 range I am using a kind of heavy pellet 31.02 gm .

Thank you guys for responding I really do appreciate the tips and comments.

Bill

[ezman604]

So you're using LED pucks? They may not be the best, in my experience. I've had better, more consistant readings with incandescent lights. I use a pair of nightlight fixtures with 15 watt bulbs. You either have insufficient lighting or some VERY nonuniform ammo.

[bmazz007]

So you're using LED pucks? They may not be the best, in my experience. I've had better, more consistant readings with incandescent lights. I use a pair of nightlight fixtures with 15 watt bulbs. You either have insufficient lighting or some VERY nonuniform ammo.

I am using the plastic pieces over the chrony I dont know what you call them they help with light. I have recessed lighting its pretty well lit. Shooting into a bullet trap its very noisy..LOL Wife is wearing my shooting muffs. 

Bill

[CitySniper]

okay...I am now convinced it is your chrony giving erratic numbers. Like Ezman said I have also tried those led push lights as well and they gave numbers about 20-30 fps higher than normal reading vs. my incandescent 40w frosted lights that I have mounted above each diffuser.

If your gun is accurate..then something is working correct, and is more consistent then your data is showing.... try shooting outside and see if your number change vs. your indoor setup


Duct seal from home depot or lowes (electrician putty) in your bullet trap will make it much more quiet and indoor friendly

[GadgetX]

Hey Bill, Chrony could be the problem.  Where do you live, maybe there is someone in the forum that is close and could help verify.

Mike

[bmazz007]

Hey Bill, Chrony could be the problem.  Where do you live, maybe there is someone in the forum that is close and could help verify.

Mike

I live in CT... I am  using plastic strips that came with the chrony Not sure what you call the they help with low light the have the rods and clip on the top of the chrony.

I hope it is the indoor lighting because its driving me crazy these erratic numbers.

[bmazz007]

Hey Bill, Chrony could be the problem.  Where do you live, maybe there is someone in the forum that is close and could help verify.

Mike

I live in CT... I am  using plastic strips that came with the chrony Not sure what you call the they help with low light the have the rods and clip on the top of the chrony.

I hope it is the indoor lighting because its driving me crazy these erratic numbers.

Not the Battery powered pucks I was talking about the plastic strips that go on the chrony medal rods. My lighting is just over head recessed lighting.

Sorry for the confusion...

[rsterne]

If your "recessed lights" are fluorescent tubes, that could be part of your problem....

840 fps wit a 31 gr. pellet is 48 FPE, and while that is reachable with a .25 cal MRod, you're not likely to get 16 shots at that power, at least not within a 4% ES or so.... more like 800-810 with those pellets for that many shots....

Bob

[bmazz007]

If your "recessed lights" are fluorescent tubes, that could be part of your problem....

No not florescent at all just 60 watt regular lights pointing down from the ceiling.

Bill

[bmazz007]

840 fps wit a 31 gr. pellet is 48 FPE, and while that is reachable with a .25 cal MRod, you're not likely to get 16 shots at that power, at least not within a 4% ES or so.... more like 800-810 with those pellets for that many shots....

Bob

Dont for get I do have the 10 spring helping me a bit. if i can get into the 820 range with these 31 grain id be happy. And get a good 16 shots staying with in a nice tight deviation I would be a happy camper the jsb kings would be in the mid 840 ish range maybe my expectations are a little to high.

Bll

[rsterne]

If you read my post.... I didn't say you couldn't reach 840 fps with the 31 gr. pellets.... what I said was that you are unlikely to get 16 shots at 48 FPE.... Heck you could probably get 1 or 2 shots at 900....

In your other thread, you mention wanting accuracy at 80-100 yards.... That will reduce the ES necessary to less than 20 fps.... and your shot string to maybe 8 shots.... PM BillG and ask him to chime in for good information on long range, high power setups for the .25 MRod....

Bob

[bmazz007]

If you read my post.... I didn't say you couldn't reach 840 fps with the 31 gr. pellets.... what I said was that you are unlikely to get 16 shots at 48 FPE.... Heck you could probably get 1 or 2 shots at 900....

In your other thread, you mention wanting accuracy at 80-100 yards.... That will reduce the ES necessary to less than 20 fps.... and your shot string to maybe 8 shots.... PM BillG and ask him to chime in for good information on long range, high power setups for the .25 MRod....

Bob

Thank you Bob this is very useful info. I think i got it now so, I can maybe get 16 to 20 shots keeping the velocity lower and say shooting at 50 to 60 yards Keeping my FPS down in the low 800s Which would work. Am I correct?

I also have a Condor 25 That attains these velocity's with ease giving me about 25 shots. Maybe i will use that for my long range  shooting and use my Marauder for 50 60 yard shooting yielding 16 to 20shots. I think i can live with that.. What velocity would be ideal do you think with the 31 gn at 60 yds 810- 820ish?

[rsterne]

Trajectory is less important than velocity spread.... You can allow for the trajectory with MilDots.... The highest velocity you can get and keep 16 shots (2 full clips) within about 3% (25 fps) would be a good choice for 50-60 yards....

Bob