Author Topic: What do you guys think is an acceptable extreme spread reading?  (Read 4254 times)

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What do you guys think is an acceptable extreme spread reading?
« on: January 20, 2007, 01:55:31 AM »
I realize that "0" would be perfect, however unrealistic, LOL, but seriously, figure:  a  novice DIY "tuned"** .177 rifle (not sure if a .22 would or should be different), springer, shooting in the upper 800's- low 900's. What would be the ES of the shots that you would be satisfied with?

** Realizing that this is a relative term in that the experts "tune" is definitely more comprehensive than that of the novice.

Offline Wallis

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #1 on: January 20, 2007, 04:43:02 AM »
now you know that the string I sent you, the gun is not broken in as of yet. It will get better, I have seen some that would do 6 ~9 ES and after they break in go to 10~12 ES all depends on the internals and the pellets used.  MY b26  for example went from 15 ES down to 6 ES then back up and stable at 9 ES. It really just depends on the gun, I would have shot the new ones more but I am out of commission again, tore my elbow tendon. it had to type one handed withoput to many mistakes

BTW  IM back, just not doing bussiness as of yet.
Wallis
let\'s all have fun at what we do

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #2 on: January 20, 2007, 05:25:15 AM »
Hi Wallis,
Glad to see ya back, and sorry to hear about your tendon hope it's doesnt take too long to heal....those things can be touchy sometime.  Please didn't think that I had asked this question because of the shot string you had sent me.  I realize that a new rifle can be all over the place and considering that, those figures you had sent were pretty darn good.  The reason I had asked this question was because I had performed "tunes" on three of my rifles ( Shadow supreme, 890S, and B-26-2).  The Shadow and B26-2 I had changed spring guides in as well.  I was just curious as to what kind of shot deviation I should be trying to achieve when tuning a rifle.  A much better/improved feel during the cocking and shooting cycle....I have that.  Though accuracy isn't really a big problem, generally, I realize that excessive deviation between shot velocities can affect point of impact at a given distance (all things being the same).  That is the thing that I've been concerned with and was curious as to what the ES range I should be "shooting" (no pun intended) for.  Now that I think of it, I probably should've posted this on the main AirGun gate forum since it is more of a generalized question, and not specific to Chinese rifles or Gamos.  I'll see if I can get it moved to the main forum.

Offline shadow

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #3 on: January 20, 2007, 05:58:59 AM »
Good to see you back Wallis :) ,bummer about the elbow :0 Get healed buddy. Ed
I airgun hunt therefore I am... };)  {SHADOWS Tunes & Camo}  airguncamo@yahoo.com

Offline daved

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #4 on: January 20, 2007, 05:16:25 PM »
This WOULD be a good post for the Air Gun Gate.  I'd like to see what kind of answers we come up with.   Hey, Wallis is still the moderator, how 'bout moving it, Wallis?  BTW, glad to see you back.

Dave

Offline daved

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RE: What do you guys think is an acceptable extreme spread reading?
« Reply #5 on: January 21, 2007, 04:47:13 AM »
For some reason I've got 20 fps stuck in my head.  My guns will do that with some pellets, but it's interesting to note that the pellets with the least spread aren't always the most accurate.  My CFX currently varies from a low of less than 20 fps to a high in excess of 100.  But I think there are a couple of other issues still needing to be addressed.  The 350 varies from about 10 to 70 fps, and is barely broken in.  Obviously, a bad pellet can skew numbers, was shooting a string the other day and was getting nice consistent mid 800's when I suddenly got one at 745.  Looking forward to what others have to say.

Dave

Offline Gene_SC

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #6 on: January 21, 2007, 10:37:48 AM »
Sure glad ya all are talking about extreme deviation. It always seems to be bug up my butt....:) Though a low extreme deviation generally should show good groups. I thinkd DaveD may be on to something there. Now I do not know this for sure but in my collection I keep a close eye on FPS and Deviation. I have a couple rifles that no matter what pellets I use the fit loose, but the deviation suffers as well. Ya gots to take into consideration though that even if you have two exactly the same guns the chances that they are both going to shoot the same, have same FPS or Extreme Deviation. I do notice that on the barrels where pellets fit loose that they are not up to par. They may fall within the norm as far as FPS but never achieve the accuracy that I feel would be acceptable for me..:)

And of course this is only my personal experiences and opinion, which we all here have a right to post... hehehe

Also I think an acceptable deviation would be in the low 20's and anything below that would be fantastic..:)

Gene
THE ONES I SLEEP WITH: BSA Lightning XL, AA TX-200, AA ProSport, BSA Ultra, HW-97K, Crosman NPSS .177, FX Cyclone, HW-30 Nicle Plated, AA-S200, Crosman Marauder, CZ-634, R-9 DG, Webley/Scott UK Tomahawk, Benji Kantana, Benji Marauder, Benji Discovery.....
....

Gene\'s Tunz n Toyz
Springer Tunin

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #7 on: January 21, 2007, 11:43:21 AM »
Thanks for moving this post Gene....I don't know what I was thinking when I posted it on the other forum gate, LOL.  
Well both you and Dave agree on the 20's figure for ES.  It's funny, but one variable that I didn't figure on was pellets of the same brand and type not fitting as tightly in the barrel as others from the same container....as I have seen this pretty often. In the future,  when I do my chrony readings, I will have to try to choose pellets that fit similarly just so they wont skew my readings due to being too loose or tight relative to the others.  Thanks guys for the information, as always you're a great help!  8)

Offline Black Mamba

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Tell ya what I've found Mer052
« Reply #8 on: January 21, 2007, 03:27:07 PM »
I happen to be paraniod enough to own a grain scale (electronic).  I've weighed many different pellets to date.  (Kodiaks and JSB Exacts being the most consistant) and I've found that pellets that don't sit in the breech snugly and pellets that have a wide weight difference shoot like poop in a horn.

Pellets quality makes a huge difference in my world.  Really.

I've found this to be true in everything from my CDT'd Shadow to my RWS 350.

If you are anal like me (hush up Gene!) you'll try to weigh your rounds and group them first.  It makes a substantial difference ( by my experience at least) that you'll see in your targets.
Lymph, v. To walk with a lisp.

Offline Gene_SC

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Re: What do you guys think is an acceptable extreme spread reading?
« Reply #9 on: January 21, 2007, 10:56:38 PM »
Had to Laugh Greg...:) And take it one more step.. hehe Look at them pellet skirts.... lol... And sometimes the skirts are distorted or defective.

There are so many variables..:) Most of my experience outside of shooting come's from CDT. He explains things to me when I am watching him work. He is a great teacher as well as a good Air Gun Smitty..:) Heck, if it was not for him, I would still be shooting Wally World pellets and getting frustrated everytime I tried to shoot something... lol

But when it comes to targets and thousand's of pellets later we all tend to learn what works best for us and our guns. :)

Gene
THE ONES I SLEEP WITH: BSA Lightning XL, AA TX-200, AA ProSport, BSA Ultra, HW-97K, Crosman NPSS .177, FX Cyclone, HW-30 Nicle Plated, AA-S200, Crosman Marauder, CZ-634, R-9 DG, Webley/Scott UK Tomahawk, Benji Kantana, Benji Marauder, Benji Discovery.....
....

Gene\'s Tunz n Toyz
Springer Tunin

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I'm all ears!
« Reply #10 on: January 22, 2007, 01:56:45 AM »
LOL, I'm anal enough to do that as well!  Grain scale, huh, sounds good to me, do you have any recommendations on brand or model?  TIA

Offline Black Mamba

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Sure do.
« Reply #11 on: January 22, 2007, 08:32:30 AM »
I bought one from here.

http://www.sportsmansguide.com/search/search.asp?r=Page%3A+%2Fcb%2Fcb.asp+KW+Box&s=SEARCH&a=search&k=pocket+scale

I have a different one than in the picture but it's essentially the same thing and it was the same price.




Lymph, v. To walk with a lisp.

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Thank you!
« Reply #12 on: January 22, 2007, 12:09:46 PM »
And the price is right! :D  :D  :D

Offline ribbonstone

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RE: What do you guys think is an acceptable extreme spread reading?
« Reply #13 on: January 22, 2007, 02:38:35 PM »
Thinking in terms of percentage is probably better...20fps  with a 600fps air rifle kind of sucks.  
Been thinking in terms of 2% as passing...over 3% kind of sucks.  So far, the single stroke pnumatics have been the closest to that mythical 0%...and you sometimes get three or four shots with the same numbers coming up on the chronograph, but long term, they seem to run closer to 1%.

With that 600fps rifle, would hope for  a bit less than 10-12fps...but on a 900fps rifle, would look for 18-20fps.
Robert

Offline daved

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RE: What do you guys think is an acceptable extreme spread reading?
« Reply #14 on: January 23, 2007, 03:34:57 AM »
Thanks, Ribbonstone, that really makes the most sense so far.  Now I need to go look at some old chrony numbers and see what's what.  And it even explains why I had 20 fps stuck in my head, the guns I concentrate on  are both 900 fps or so.  Later.

Dave