Do you get fed up of hearing that a certain pellet is best for a given rifle ?
or that the rifle works great but every now and then gets a "FLYER" or why a rifle doesn't work as well with the latest batch of pellets that worked fine before !!
So what's changing, apart from the weight and the profile of the pellet, your rifle should be able to send constant POI's regardless of what pellet you choose.
(Excluding of course a tin of highly oxidised or bent and irregular made pellets).
So here is what everyone can do. Find out what size skirt suits your rifle best for any given pellet..take a tin of pellets, any tin of pellets and after a quick visual check for bent skirts and slag or deformations, let's get started
What we need to do is to sort the pellets, and set them into separate piles sorted by skirt diameter size...now there are several ways to do this, the best is using a sensitive dial gage and setting it up over an anvil or flat surface and this can be done many ways. set the dial up for zero when using a 4.5mm or 5.5mm (177 or 22) feeler gauge. re test this measurement several times as this reference is very important.. the dial gauge should rest when there in no pellet being measured at a figure under the calibrated reference size so that it can measure under size skirts as well.
If you do not have a dial gauge then a caliper gauge will work but it's more difficult as you can squash the skirt if you apply too much pressure.
Or if you have no such tools then do a roll test..on a flat surface align the pellet facing left to right on a line. it helps if the surface is slightly tilted forward to allow the pellet to roll away forward from the line. By tracing the curve of the trajectory of the pellet as it rolls you can mark the curve and draw five or six different lines and use that to group the pellets..
OK now we can group the pellets from one batch into different tins marked -0.05, 0, +0.05, +0.10, +0.15,+0.20 thousands of a mm . make sure that the tins are clearly marked.
Next, set up a table with a solid rifle support or vice so that the rifle can be accurately aimed at the same point for each shot..i can even do this with a pump rifle, set your scope to the highest gain..and decide on the power level you are going to use for this test. the power level has to remain constant for 100 shots. the minimum required for a realistic evaluation of a batch of pellets..never correct the aim if they are off to one side, just keep aiming at the centre of the target.
next we set up a target card at 10 meters or 25 meters in an area away from wind. so a calm day (or nite) is best unless you have an indoor range.
shoot each tin of sized samples using them all on their own target and clearly mark the target card, make of pellet, weight, model, and measured skirt dia over stock ( the reference size either 4.5 or 5.5mm if using metric) . so if you only have 5 pellets that measured -0.05 then that all you can put into that target, then change the target and try the next batch.
You can use a multi target card like the 25 foot ones with 5 different roundels and the two logo roundels either side giving a total of 7 points of aim for one card..
Just keep aiming at the center of the target and take your time for each shot, relax and make each one the best you can do...then with the next tin of sized samples do the next target roundel etc etc making sure to record the amount of each size as well for reference,,, eg 5pellets at -0.05, 10pellets at 0.0, 22 pellets at +0.05, 54 pellets at +0.10 etc etc.
by using 100 taken at random from the tin or even better all 250 if you can, you will be able to record the percentage of optimum pellets in that tin..and now measure the spread for each group of sized pellets....
You should now have a set of targets that will show why you get flyers, as one size will be all over the place, others better and one size in particular will be a super tight group as good as your best ever group done with that rifle ever !!! You will be elated, and want to get drunk at this point as this is the big breakthrough you have been waiting for...!!
So now you know the best skirt size for that particular pellet in that gun, for that particular power setting. ..all you need to do is to make a pellet resizing tool to resize all the pellets into that sweet spot diameter and you will be able to get fantastic groups from every pellet!!! Now you can try a cheaper pellet or one that loads easier but gave erratic results and do the same test. over and over again with every new make or model of pellet you should repeat the test and you will soon find that sweet resized pellet that gives you killer accuracy...
I made my resizer by machining a disk of aluminium (dural or hardness over 250) making a tool that fits onto an empty tin ( i actually used an old tin of 500 concord pellets as the tin is deeper and you wont crush any pellets when they go through the holes.. my resizer is only 2 cm deep with a recess of 5mm on the top side and 3mm underneath to protect the holes when the tool is being transported.
I machined down from 5mm inside the edge down to a depth of 5mm to make a flat dish inside the disk, then i drilled two concentric rings of holes of the required diameter 10 in all and i you then just give each hole a tiny chamfer about 0.5mm on both side of each hole. mine are +0.05mm for diablo by rws in 177.
Just pour in a handful of pellets into the resizer and shake the tin in a circular motion. All the pellets will just drop nose first into the holes and sit there, one by one you use a pointed tool, to push the pellet through the hole, and when it emerges it is the correct skirt diameter...make a pusher tool by reshaping an old screwdriver on the grinder and have a taper of 1" or 2cm from the shaft dia 4mm down to a blunt point so that it fits into the back of any pellet type..by using a shaft thats 4mm dia it can be used for all the resizing tools you make, 177 and 22 the tool will work.
How accurate are the results..well i have a wasp nest in a wall, but i can't get near them as their so aggressive...so i have set up my shooting table in the barn 12 meters away and can pick them off one by one as they emerge from their nest..thats hitting a moving target at 12 meters or just under 40 feet...and it's fun...with my modified Rebel 4.5mm and a 6-24 x 50mm scope. pellets are rws diablo basic 177 resized to +0.05mm
comment, you will find that 90% of them were over +0.05 and mostly around +0.20 for `that particular pellet. so as my rifle loves +0.05mm i can resize a complete tin of 500 pellets in half an hour and no rejects, no flyers, and superb accuracy, and using one of the highest quality but low priced pellets for 177;
My other REBEL SS 0.22cal also uses +0.05mm with gamo match and gamo magnum pro, so with just two dies, i can reform pellets for both rifles.
Now you have found the sweet spot in size it's time to repeat the test on four targets and varying the power, most pcp are adjustable and the pump up rifles can be pumped to whatever power you want,,,so try 20 rounds at 200 mps, then 20 at 225, then 20at 250, and so on up to 300mps and see which power or speed gives the best accuracy...again do this in a sheltered area away from wind, you want to find the optimum speed for accuracy then it's up to you to compensate for windage not just go to full power to reduce flight time trying to reduce the affect of the wind...now you will be able to get the best from your rifle as far as the pellet accuracy goes...
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