Pellet grouping issue – what are your thoughts?
I was testing pellets this weekend. Decided to set my .25 Condor up to shoot JSB 25.4 and experienced some odd pellet grouping I’m hoping someone can explain to me as to why. ❓
I don’t know if this has any impact (pun intended) but per the Quick Reference section and other sections of the forum, the “sweet spot” settings had my top hat at .092 and the power wheel is set at 3.7. Previous crony testing showed me that a starting pressure of 2600psi should get me close to the top of the curve. These settings gave me 20 shots starting at 1017fps peaking at 1037fps and ending at 998fps. 🙂
Now to test grouping. I set my targets at 50 yards in a virtually no wind condition. I shot 4 – 5 shot group tests and was getting some lousy grouping. 🙁 Didn’t measure but rarely was I getting two touching each other and a wild guess would be about 2″+ apart. The spread was almost always horizontally, and sometimes a little vertical.
Believing it was more my inability to steady the rifle on the rest well enough this outing than rifle or pellets to shoot accurately, I decided to play with mil-dot holdover Chairgun IPhone app 😎 indicated I should be getting at so I moved the targets out to 75 yards. I recharged the tank, made no adjustments to the rifle.
“Chairgun sez” 2 mil dot hold over. Now my 5 shot groups are 1” ❗ 😯
My question is, why do I get a “shotgun” spread at 50 yards and tight grouping at 75 ❓ ❓
As a foot note, I experienced the same type of grouping when shooting my .22 Marauder using .22 Discovery pellets. Terrible groups at 35 to 50 yards at 60 to 75 the groups tightened up significantly. With the same rifle under same conditions, using JSB 18.1g the groups actually broaden out as might be expected.
Any thoughts on why some pellets tighten up at farther distances.
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Nflshop20 WTF 😯 😯 😯 😯
You can do it with a tight patch also or a pellet you smashed down so you have to force it into the breech. Then push it in with a cleaning rod. it should have the same resistance to push it thru the barrel until you get to the muzzle where it should be tight.
Mine was tight for two inches then loose, it fall down the barrel, then tight again at the muzzle where the choke was.
Regards,
Roachcreek
‘Noid – sent you a pm about your pw/tophat settings for JSB’s. Thanks 🙂
Ssshooter – Good point about the scope. Improper parallax will definitely have an effect on the aim point/impact point. I followed the “How to set Parallax” article when I mounted the scope I’m using It is a BSA Stealth Tactical 6-24×44 with side AO. http://www.bsaoptics.com/scope.aspx?productID=295
Does anybody have good/bad experience with this scope? Feedback appreciated.
I checked the side wheel yardage and compared it to what my Simmons 600 range finder indicated and it’s within 5 yards. Focus was good, didn’t appear to parallax but I didn’t “eyeball” it either. However, I am still going to check the parallax possibility when I go back later this week. I’ve also have a Simmons 4×24-42 side AO scope on my MRod I may try just for kicks.
Roachcreek – Slug the barrel?? Please elaborate. 😕
I had the same problem, I had a bum barrel.
My breech was tight, no jokes now, and then the bore was looser until it got to the choke where it was tight again.
Only Kings shot well, the thin skirt allowed them to expand twice, but I still had troubles like your having.
Slug your barrel and see.
Regards,
Roachcreek
Sounds like you have a scope with fixed parallax at 100 yards… Anything closer than 75 is likely to scatter as your eye isn’t in the same fixed position. Closer to 100 and things will tighten up.
Buy a quality $250-$400 Adjustable Objective (AO) scope and never look back… I like the Burris Timberline (AO) and Weaver Rimfire (AO) scope range. I have them on both my AGs and never question zero when I pick them up.
http://www.burrisoptics.com/timberline1.html
http://www.weaveroptics.com/optics/riflescopes/classic_rimfire/
Yes it would, then find out who put the magnet in you pellets and target. 😯
I have much better accuracy shooting those pellets in the mid-900’s as my peek. To shoot those speeds my tank is filled to 2100 to start.
AG1- Did not get to go back and shoot 50 again. Had to get to work so I can have more airguns 😆 I will go back and try 50 again, probably on Wednesday. Great 💡 though. Glad somebody’s thinkin.
Did not change a thing after the first 20 some shots not so much as a click on the scope. Just charged up the tank.
It just weird the same thing happened with the .22 Discovery PCP pellets. Suck up close; tack drivin at a distance.
Another thing I want to try is maybe 90 – 100 yards. Wouldn’t it be 😆 if I start getting dime size groups at that distance.
After you shot wide spreads at 50 and then shot close spreads at 75, did you come back to 50 to shoot again ? You need to confirm your first failure. Mostly likely your re-attempt at 50 would be close groups, because whatever you didn’t do right at first, fixed itself on the second attempt, else what you adjusted would manifest itself again.
hmmmm.. Scope adjustments, different postioning, etc. ???
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Ya know, I still contend that (and I posted elsewere in the forum) that before you can post on the forum must answer 5 questions about air rifles.
Like:
Name one Airforce rifle 😕
What are most pellets made of 🙄
How do you make the gun fire 😛
Who is Tony 😎
Is PETA important to me 😆
Simple stuff. Questions even I can answer.