Pellet sizes

User avatar
Posts: 3037
Joined: Sun Feb 15, 2015 6:20 pm
Location: Nuneaton

Pellet sizes

Sat Apr 28, 2018 7:38 pm

So what size pellets are we using
All of my Air Arms use 4.52 which I’m happy about.....but who uses 4.51 and 4.53’s :shock:

Did I mention that I'm the only one to have attended EVERY annual meet since we started

no avatar
gary martin
Posts: 682
Joined: Thu Feb 19, 2015 8:21 pm

Re: Pellet sizes

Sat Apr 28, 2018 7:49 pm

given manufacturing tollerances and repeatability, I find the notion of head size a little bit of a fairy story. if I believed the head size quoted I would do the same for the quoted weight. the only advice is not the head size, but the die number. get a batch which suits the barrel of your weapon, and buy a shed load of them. but as you ask my current batch has a quoted uhumm head size of 4.52mm dia and a quoted uhumm weight of 7.88 grain.

no avatar
Posts: 44
Joined: Mon May 29, 2017 10:55 am

Re: Pellet sizes

Sat Apr 28, 2018 10:50 pm

I agree with Gary.

I bought a PelletGage and have measured over 50 pellet types and die numbers. Actually I measure weight, length and head size. JSB quoted sizes are pretty meaningless but within each batch (and different batches from same die) are more consistent than other manufacturers. H&N 'sized' pellets (e.g. FTT 4.51/4.52/4.53 or BM 4.51/4.52/4.53) average sizes are often closer to the stated size but show more variation within a batch.

Let me demonstrate the issue with JSB quoted sizes: I measured Weihrauch FT-Exact die 8 and JSB Exact die 8. Both were the exact head size, length and weight but the FT-Es are sold as 4.51 and the JSBs as 4.52.

The biggest difference between JSB batches is the length, which for 8.44gr can be from 5.97mm to 6.38mm. But the difference within a batch will be less than +/-0.02mm. It's possibly the best indicator of whether pellets come from the same die... and the easiest way to sort pellets if you accidentally mix pellets from different dies.

no avatar
Posts: 587
Joined: Tue Feb 17, 2015 8:13 pm
Location: Ferryhill Co Durham

Re: Pellet sizes

Sun Apr 29, 2018 5:32 pm

I shoot mainly an s410 in .22. It likes AA field in 5.51. If i use 5.52 i lose the acurace over 25yards. This sounds odd but it does happen. I can not believe the small difference in size could make such a big difference in acuracy.

no avatar
Posts: 291
Joined: Mon Feb 16, 2015 2:37 am

Re: Pellet sizes

Tue May 01, 2018 1:51 am

Test different die #'s and buy all you can afford, when you find the right one. Make sure to test at 55 yards and in a breeze. I have 20,000 pellets that are great in calm air, but pretty much crap in a light breeze.

Post Reply

Who is online

Users browsing this forum: No registered users and 0 guests