.177 pellet dia. (skirt??) by .001" increments?

Moderators: pilkguns, Marcus, m1963, David Levene, Spencer

Post Reply
Keeley
Posts: 170
Joined: Fri May 28, 2010 9:05 pm

.177 pellet dia. (skirt??) by .001" increments?

Post by Keeley »

Here goes. I'm new to this game. Because one of my shooting buddies was nice enough to bring one of his air rifles to the range when we were shooting rimfire and it shot so good and you can shoot in the back yard, I decided I had to have one. Being LH'd I bought a nice little Walther LGM2. It shoots great. The trigger is out-of-sight.

Question: When shopping the web for pellets I often see them advertised as .177 in .001" increments. Being I do this as a hobby I'm sure it doesn't make a difference at this level but am courious as to what this diamention applies to?

T
Rover
Posts: 7048
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Post by Rover »

The head size. You're right, it doesn't make a difference.

The only way to determine pellet accuracy is by empirical testing. There is more variation from lot to lot of the same pellet than between head size or brand.
BigAl
Posts: 312
Joined: Mon Nov 26, 2007 5:37 am
Location: Norfolk England

Post by BigAl »

Just for interest I took 20 pellets randomly from at tin of RWS R10 pellets which I think are nominally 4.50 mm, although they could be 4.49 as our club has both sizes and the details on the batch label have worn off, it's a nearly empty tin. I measured the head size with my cheap digital calipers and got the following results:

Code: Select all

Average	4.462
Mode	        4.46
Median	4.46
Ave Dev	0.0086
Max	        4.48
Min	        4.44

4.46, 4.46, 4.48, 4.46, 4.47, 4.47, 4.46, 4.46, 4.47, 4.46,

4.45, 4.46, 4.46, 4.44, 4.45, 4.45, 4.47, 4.48, 4.48, 4.45

Hardly a through scientific experiment, but enlightening all the same. even if they are 4.49, not the 4.50's I think they are none of them made it even to the nominal head size. These are though a quality pellet and what is pleasing and probably the most important is that the head size average deviation was calculated to less than 0.009 mm, which is actually smaller than I could measure with the equipment I was using. I have used metric measurements as that is what the nominal head size is specified in.

I do not think it makes too much difference to the accuracy of the rifle which head size you pick, as long as they are a good quality pellet and that whatever the size and weight actually is it is as consistent as is possible. I would normally get 4.49's for my daughters Walther LG400, but only because the test card that came with the rifle was shot with RWS R10 in 4.49. (Walther indicate on the certificate which head size was used in the test). We pick the pellets straight out of the tin too. selecting and sorting pellets may be of advantage at some point, but I would think she would need to be shooting 390 plus regularly for it to possibly make a difference to scores.

Alan
Keeley
Posts: 170
Joined: Fri May 28, 2010 9:05 pm

Post by Keeley »

Thanks for the quick responses fellas. Onward and upward.

T
Rover
Posts: 7048
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Post by Rover »

BTW The pellet size shown on the test card is meaningless. You can't buy the pellets they used and they shipped the gun with the first test card where the pellet shot OK. They don't test pellets for you.
rmarsh
Posts: 220
Joined: Mon Jul 02, 2012 8:31 pm
Location: Arkansas

Post by rmarsh »

As an answer to the OP, since you are not shooting serious competition, as rover stated; head size makes no difference.

For the more serious, here are some observations from my own testing. I regularly test pellets in my daughter's rifles. (LG400 (s) and FWB 800). In the last year I have tested over 100 lots of pellets of most of the premium brands. Mostly R10, H&N and JSB.

One great 10 shot group is not enough. I have had lots shoot an awesome group only to be followed by a so-so group. For the lots that show promise, I usually shoot at least 5 and often 10, 10 shot groups.

All the guns I have tested seem to prefer 4.49s but I have found several lots of 4.50 and 4.51 that shoot great. Recently I found a lot of 4.48 that shoots great in one rifle.

For no obvious reason, some lots shoot great others terrible. Just because a lot shoots good or bad does not usually indicate it will do the same in a different rifle.

For whatever reason rifles change. I have found that a few months later, a lot that shot great may not shoot great anymore. The velocity is the same, barrel clean, but the lot of pellets it likes is different. For that reason, I keep 5 or 6 lots of pellets on hand that shoot good in a specific rifle. A few days before a major competition I test those lots and select the lot that is shooting best.

If you are a serious / high level shooter (or parent of one) test often and test a lot. It does matter.
45ACP223
Posts: 246
Joined: Sun Sep 15, 2013 11:03 pm
Location: The Sunny South

Post by 45ACP223 »

That brings up pellet sizing. For 10 meter league competition (not college or olympic trials), is it worth while to size pellets? Does sizing only make the skirt uniform, or does it also make the head of the pellet more uniform? I've had several folks at our club say sizing doesn't really help in accuracy and would like to know what the real pellet shoots here think.
WesternGrizzly
Posts: 278
Joined: Sat Jan 09, 2010 10:43 pm

Post by WesternGrizzly »

At the league/Club level, there is no reason to size pellets. Even if you are shooting 598+ the time would be better spent working on other things.
I have only heard of one person who shot at the Olympic level to sort their pellets, and it was by weight and visually.

I agree with rmarsh on pellet testing regularly. I had a lot of vogel pellets that shot wonderfully in the begging, but soon they wouldn't hold a decent group. I cleaned my rifle, sent it to the shop, and they still don't shoot as well.
Matt
User avatar
RobStubbs
Posts: 3183
Joined: Mon Mar 01, 2004 1:06 pm
Location: Herts, England, UK

Post by RobStubbs »

Some guns prefer a smaller or larger size, but the only way to tell is to batch test them. I only shoot 4.50's in my AP's as 4.49's feel slightly loose, although that's what the guns were test fired with. At the elite level I'd be inclined to batch test, epsecially if shooting rifle. As for skirt sizing, it's a waste of time. If you buy good quality pellets the difference is insignificant.

Rob.
rmarsh
Posts: 220
Joined: Mon Jul 02, 2012 8:31 pm
Location: Arkansas

Post by rmarsh »

I have never tried "sizing" pellets so I have no personal experience. I suspect the time and effort would be better spent lot testing more pellets.

I do visually inspect pellets with a lighted magnifier lense. I also sort them by weight. For example, I recently sorted a tin of H&N 4.48s. I sort them into 3 groups. 7.98 - 8.02, 8.04 - 8.08, 8.10 - 8.14. The middle weight typically has the most that fall into that range.

I discard all pellets that weigh above or below those ranges. That is usually 10 to 30 per tin. Some will weigh as little as 7.80 some as much as 8.20. I tend to discard another 50 to 100 that are dented or bent.

Does it matter? I don't know & my testing is inconclusive. In this day of decimal scoring just a tenth or two per string adds up. .4 to .8 is often the difference between 1st and 2nd... or maybe 1st and 5th.

It's very time consuming & I only do it for important matches. The rest of the time she shoots them straight out of the tin.

It may not help.... but it can't hurt!
robf
Posts: 367
Joined: Thu Dec 14, 2006 6:24 am
Location: South, UK
Contact:

Post by robf »

If anyone measures the head size of a pellet they will most likely find the head size is a nonsense compared to the actual measurement.

I haven't tried it with other brands, but JSB domed pellets are normally 4.49-4.50 no matter if it says 4.51,2,3 on the tin.

Batch is more important to performance. But it's unlikely at 10m you're going to see an improvement especially when combined with the shooting position, by sizing. Unless you're shooting 600's and losing 9.9's by purely the pellet it makes little odds as the performance increase by sizing isn't enough to get you a 9 over an 8... or a 10 over a 9.

Shooting at 50m there's marginal increases to be found, but it depends on the barrel and pellet to determine the best size, which can only be found by experimentation. But to date, sizing, lubing, and weighing haven't yielded benefits at 50m that can't be out done by simply finding a better performing batch.
45ACP223
Posts: 246
Joined: Sun Sep 15, 2013 11:03 pm
Location: The Sunny South

Post by 45ACP223 »

Thanks guys for the input on sizing.
Rover
Posts: 7048
Joined: Sat Nov 15, 2008 4:20 pm
Location: Idaho panhandle

Post by Rover »

In my testing of pellet sizing using a Nygord sizer and a Steyr LP1, I found that in EVERY case the group size increased.

Don himself told me his sizer didn't work and that he only sold them because people bought them.

I should mention that the "feel" of the pellet as it's seated (tight or loose) is unimportant. The barrel is relieved to varying degrees to allow insertion of the pellet, which is then blown into the rifling while the skirt is expanded and then sized to bore diameter by the bore.

rmarsh....Get a life!
TexasShooter
Posts: 72
Joined: Sun Jun 06, 2010 2:39 pm
Location: Texas

Post by TexasShooter »

rmarsh wrote:
I discard all pellets that weigh above or below those ranges. That is usually 10 to 30 per tin. Some will weigh as little as 7.80 some as much as 8.20. I tend to discard another 50 to 100 that are dented or bent.
What scale are you using to weigh the pellets?
jhmartin
Posts: 2620
Joined: Mon Nov 29, 2004 2:49 pm
Location: Valencia County, NM USA

Post by jhmartin »

Rover wrote:rmarsh....Get a life!
In defense of Rick....
1) He's an engineer's engineer with lots of patience (i.e. uber-engineer)
2) He's got the time
3) He's got a daughter that is a world class shooter, and when scores are counted in tenths these days, his selections may indeed make the difference in this shooter between a world cup slot or not ......

(Note ... he's as nerdy with .22 ammo as well!)
rmarsh
Posts: 220
Joined: Mon Jul 02, 2012 8:31 pm
Location: Arkansas

Post by rmarsh »

Texasshooter, I use a Sartorius AY123 lab type scale. It has a resolution of 2 one hundreths of a grain (.02). I sort in groups of .04 to .06 grains for both pellets or .22lr. Overkill, yes.... but you have to weigh them all to find the 1% that are way light or heavy, so I just go ahead and sort them, can't hurt.

Well, Rover; I DO have a life.... it is devoted almost full time to helping my sweet, little, petite 15 year old daughter be the best person and best shooter she can be. If you think I am nuts on weighing ammo, you should see my training plan(s) and records!!!


jhmartin wrote:
Rover wrote:rmarsh....Get a life!
In defense of Rick....
1) He's an engineer's engineer with lots of patience (i.e. uber-engineer)
2) He's got the time
3) He's got a daughter that is a world class shooter, and when scores are counted in tenths these days, his selections may indeed make the difference in this shooter between a world cup slot or not ......

(Note ... he's as nerdy with .22 ammo as well!)
Thanks for the "defense" Joel! I deserved that little jab from Rover...... He's right, I get a little too wrapped up in the details some times, but I'm having such fun doing it!

Now, I've been called "nerdy" and "geek" all my life and wear those titles as a badge of honor. "Uber-engineer" is a new one...... I kinda like it! I think I still prefer "eccentric", sounds so esoteric and Einstein'ian don't ya think? LOL!! See you in few days!
jhmartin
Posts: 2620
Joined: Mon Nov 29, 2004 2:49 pm
Location: Valencia County, NM USA

Post by jhmartin »

What your daughter should get you:
http://www.cafepress.com/mf/16183975/ub ... d=91671990
in a nice polo golf shirt
MatS
Posts: 11
Joined: Thu Apr 25, 2013 11:34 am

Post by MatS »

Last two seasons I'm shooting JSB (http://www.schulzdiabolo.cz/en/pellets/match/) the 4.49 middle weight (yellow) ones with a Walther LG300xt. The testing group is actually (very very tight) perfect with this ammo at a speed of 177 m/s at the first batch. Years before it shot the HN match pellets with 4.48, testing with a bit of struggle but the final testing group of the chosen batch was, again, perfect.

All Walthers (two LG300xt and one LG400) I've sen had no problems with ammo testing (the groups were so tight, the pellet wouldn't even fall trough itself), while all newer FWB (a couple of 700's) struggled very hard with testings groups and the results aren't satisfying at all (the best groups were at least around 6mm wide), while the older FWB (some P70) shot good as the Walthers.

What I've seen and expirienced the speed has by far the most influence on the tightnes of the group as any other parameter.
redschietti
Posts: 386
Joined: Sun Apr 03, 2011 4:31 pm

Post by redschietti »

This whole discussion reminds me of a Tshirt I saw once.

"Sorry, we worked harder than you"

I know Marsh puts in the work
Post Reply