head size

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conradin
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Joined: Sun Apr 29, 2012 1:18 am
Location: Basement.

head size

Post by conradin »

What is the difference between various .177 pellet head size, ie, 4.49, 4.5, 4.51, 4.52 etc. It also seems like anything that is 4.53 or beyond is for field targets.
Rover
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Location: Idaho panhandle

Re: head size

Post by Rover »

The higher the number, the fatter the pellet. It seems to make absolutely no difference. Only testing of individual pellet batches will allow you to determine best accuracy.

Just remember: Good head is hard to find. (Or is it: Hard head is good to find.)?
Brazos
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Joined: Thu Jun 09, 2016 9:28 pm

Re: head size

Post by Brazos »

Yes it does make a difference. The head size is the head of the pellet, not the skirt. I personally have not experimented with it for 10M as I am not good enough at 10M to make any kind of difference. I do shoot field target where we shoot out to 55 yards and at that range you see the difference. The problem is a tin of pellets may be labeled as 4.50 (for example) but the pellets in the tin could be mostly something other than 4.50. That means if you know your rifle has it’s very best accuracy with a particular pellet in 4.50 head size you would need to measure/verify the pellets in the tin you bought are mostly 4.50. I don’t have the time or inclination to do that. If I am having accuracy problems with a new tin of pellets I may check the head size. Here is a real world example of that. I experimented with many different pellets with one of my field target rifles. Most all pellets shot well at 30 yards but at 55 yards I found Crosman Premier Heavy pellets were lights out. So I ordered a bunch more pellets. The new pellets weren’t too great. What I found was the Crosman Premier Heavy pellets that shot great were labeled as L Lot and the measured head sizes were pretty consistent at around 4.50. The new CPH pellets I bought, that did not shoot as well, were labeled M Lot and I found the head sizes I measured were consistently around 4.54. I was somewhat impressed with Crosman’s head size consistency within each die lot (I have measured JSB, H&N, etc that have been all over the place) but unfortunately for me the new die lot no longer agreed with my rifle. That’s why when you hear of someone finding a die lot of pellets their rifle likes they try to buy as many of that die lot as they can before they are gone. In my case the head size dramatically changed from one die lot to the next and L Lots were no longer to be found. You did not give any background in your question but I assume it is related to 10M. 10M your distance is much shorter than 55 yards so mixed head sizes may not be as noticeable at that short or range. If you are shooting at 55 yards, perfect conditions, with a great rifle and get that flyer or two that ruins a great group then head size could be the issue if there are some outlier head sizes in the tin of pellets you are shooting. I really enjoy shooting 10M but at my skill level I consider it a victory to put all my shots in the black. At my skill level worrying about head size is a waste of my time. That’s time I need to be shooting to get better to a point that maybe head size does make a difference.
spektr
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Re: head size

Post by spektr »

In my 777 it seems to matter. The gun is not a powerhouse compared to a PCP gun, and it needs all the help it can get to be consistant. I notice better groups when the bolt pushes the pellet into the gun with a bit of snuggness. I notice the snuggness is more prevalent in cans marked with a larger head size. My Vogels seem to be on the stated diameter more often than not. For some reason, their Orange Practice pellets are the best performing stuff I have shot thru it. Go figgure. I dont measure every tin, i feel how it loads. I havent had a tin with enough variability in closing feel to make me change away from it, but Im not shooting this gun for scores much any more. Ultimately it is a point difference, maybe, but the consistant feel probably soothes my mind more than there being a measurable performance difference....
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conradin
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Re: head size

Post by conradin »

I have just ordered a couple of JSB light 4.52 pellets. I shall see what sort of difference it has to my 4.49 R-10 or my regular JSB 4.5 Match.
william
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Re: head size

Post by william »

conradin wrote: Thu May 20, 2021 3:48 am I have just ordered a couple of JSB light 4.52 pellets. I shall see what sort of difference it has to my 4.49 R-10 or my regular JSB 4.5 Match.
The results will probably reveal more about the test protocol than about the different pellet sizes.
Rover
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Re: head size

Post by Rover »

What William, in his ever over-polite manner, is trying to say is, you'll probably fuck it up.
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conradin
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Re: head size

Post by conradin »

My job at the range, as part of my primary duties, is to zero in and to bore sight customers' rifles. Needless to say, I also have to test the weapons and make sure they pass the test. I would sign weapon ID cards to prove that they passed the test and there is no need to have a test again unless they changed the configurations afterwards. This is a safety procedure.
I may not be a competitor, but at least I can do is to test the weapons and do emergency repair. In short, I cannot afford to fuck it up.
Last edited by conradin on Fri May 21, 2021 9:15 pm, edited 1 time in total.
william
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Re: head size

Post by william »

I'm impressed by everybody who knows what I mean. Is it possible that I may have written precisely what I mean, or that I meant precisely what I wrote?

Wasn't the point made pretty convincingly by somebody years ago (Steve Swartz, maybe?) that whatever one thinks he knows after testing goes down the toilet when a new lot is introduced?
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conradin
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Re: head size

Post by conradin »

conradin wrote: Thu May 20, 2021 5:46 pm My job at the range, as part of my primary duties, is to zero in and to bore sight customers' rifles. Needless to say, I also have to test the weapons and make sure they pass the test. I would sign weapon ID cards to prove that they passed the test and there is no need to have a test again unless they changed the configurations afterwards. This is a safety procedure.
I may not be a competitor, but at least I can do is to test the weapons and do emergency repair. In short, I cannot afford to fuck it up.

Sorry Rover, I mis-read your post.
spektr
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Joined: Mon Jan 21, 2013 9:53 pm

Re: head size

Post by spektr »

william wrote: Thu May 20, 2021 7:22 pm Wasn't the point made pretty convincingly by somebody years ago (Steve Swartz, maybe?) that whatever one thinks he knows after testing goes down the toilet when a new lot is introduced?
Perhaps, It actually depends on what was learned. If we learned that larger diameter heads shoot better overall in specific pistols over time. I would not expect that to change. If we were in possession of a killer lot of soft skirted wonder pellets, I can see your point. In any case what was learned and how it relates to individual lots has a range of answers, and how those answers are applied depends on our skills at seperating the fly shit from the pepper, and THAT is where the artistry is........
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