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Old 26th January 2014, 08:23 PM
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Conor Conor is offline
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Unless your sizer is less than 4.48mm you are not sizing the head, most sizers just size down the skirt diameter.
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Old 26th January 2014, 09:37 PM
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If you guys want to do tests with sizerís and pellet measurement first buy a good calliper or micrometer donít use Chinese stuff, after a Mitutoyo Iím starting to change my thoughts.
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Old 27th January 2014, 04:38 PM
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Conor's correct, it depends on how small your sizer is.

Most will just size the skirt as it is larger than a pellet head and it can be clearly seen using a magnifying or jewellers glass.
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Old 27th January 2014, 04:45 PM
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Default So...

You guys arw saying we size the skirt
Which get blown out into the bore by compressed air
Which resizes the skirt to the dia of the bore
And is then maybe reized again if we have a choked barrel

Which kinda makes the whole process a complete waist (pun intended:-)) of time
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Old 27th January 2014, 05:29 PM
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Originally Posted by dave croucher View Post
You guys arw saying we size the skirt
Which get blown out into the bore by compressed air
Which resizes the skirt to the dia of the bore
And is then maybe reized again if we have a choked barrel

Which kinda makes the whole process a complete waist (pun intended:-)) of time
Depends if your skirt is round, or oval, leaks air past and doesn't inflate centric to the pellet. And then the next pellet does something different... loose fit, starts moving before it inflates.

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Old 1st February 2014, 11:30 PM
planner planner is offline
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Originally Posted by Tone View Post
I have recently gone through a phase of sizing pellets, that was until I found a reduction of over 20 ft/s (over .5 ft/lb) between with the sized pellets compared with those strait out of the tin.

I can only put this down to the sized pellet skirt not blowing out against the barrel wall the same as the unsized one and therefore not creating such a good seal.

Has anyone else found the same thing happening?

I found a better way (for me at least) in a benchrest article in a back copy of Airgun World. Instead of pressing pellets through a sizer, sort them through a gauge. That way, you don't deform them and they don't lose velocity. If you just want to plink, then shoot them straight from the tin and you don't get caught up in the loop of having to reset your zero to accommodate sized or unsized pellets. That's why I only do this with weighed pellets for that special occasion ...

You make the gauge from a BIC Cristal stick pen (I think it only works with the BIC) - it must be the see-through tube type though. Strip out all the bits, including the end cap, which just leaves you with the tube. The hole down most of it's length is the right size to take a .177 pellet, except for a tapered part near the pointy end - that's your gauge. Take a pellet and first check the skirt is round, then insert it into the tube and let it gently slide down (rather than drop down) inside until it sticks in the tapered part. I do mine skirt first, but the choice is yours. Make a mark on the tube with a fine point marker in line with the skirt. Tip the pellet out by knocking the tube on a pad of paper or magazine. I use a Post-it note pad. NOTE - the steeper the angle of the tube when you insert the pellet, the harder you will have to knock to get it out! Put the "gauged" pellet into a container - I use an old plastic ice cube tray for segregating both weighed and gauged pellets. Now repeat with the next pellet. If it sticks at a different place then make another mark on the tube with your marker. TIP - make successive marks in a spiral around the tube so that your view of the pellet is not cluttered. Don't get carried away with too many marks - I have only 4 on mine and they are about 1 mm apart. After you've sorted a few dozen in theory you should have all the graduations you should need. Give each graduation mark a number for clarity and that's it - you've got your gauge.

If you use a wide range of pellets you may need to make more than 1 gauge. In the past I used mainly AA Diabolos and I found they varied within 4 different skirt sizes - hence my 4 graduations. Now I shoot mostly JSB Exacts (including Express) and find they mostly fall into only 2 sizes - per tin that is.

All I can say is, this works for me and I pass this on for what it's worth.

Cheers all.
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Old 18th February 2014, 07:17 PM
Silversurfer Silversurfer is offline
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Default Pellet sizing

I have a 4.49 (head size) sizer and have tried sizing, weighing, weighing and sizing.
I tried 10 pellets straight from the tin and the variation was 6fps.
10 weighed, variation was 5fps.
10 weighed and sized, variation was 4fps.

I can't say if it makes any difference to group sizes as I haven't carried out any testing.
I have found that the weight and sizes stated on the tins are seldom more than a very rough guide although the very best quality match grade wadcutters like RWS R10 and H&N Finale Match are very good weight wise.

I'm at a loss as to what the size marking actually refers to as I have tried several sizes 4.49, 4.50 and 4.52 back to front or head first into the bottom of the sizer which measures 4.49mm and they all drop in up to the skirt.

My opinion (for what it's worth) is weighing and checking for deformed skirts is worthwhile.
Sizing? Not sure, maybe with cheap pellets with poorly formed skirts it would improve performance but there are many factors to take into consideration, as we all know, what suits one barrel may not suit another.

Accurate shooting is all about eliminating the variables so it's worth a try I suppose.
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Old 18th February 2014, 08:51 PM
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Default Size pellets

I have a 17inch sizer it's my barrel , I take my pellets out of the tin slide it into her and let it rip the barrel dose the rest of the work ... It works a treat

Regards Dave
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Old 19th February 2014, 08:43 AM
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If you size pellets its only in one direction, 'down', which will usually cause a loss in perceived power, due to this power being diverted to/lost in the reforming of the pellet to fit the barrel.
you need to accurately measure the internal dimensions of your barrel to find the correct size you need, otherwise your just wasting your time. I believe it is any way.
Just find a batch that shoot well, then select out the best, ... head damage is critical, tail damage....not so much.

Weight also plays a part, but you dont need to be anal, jut discard the overly light or heavy within the tin.
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