Unusual powder choices seem to work in the tac20

[craigyboy]

I was out today testing some powders for the cooper tac20, I have been stuck for powder choice and ended up having to use less than suitable powders I was surprised with the results to say the least.

 

The way i usually load test a new powder is to load 11 rounds with the powder and bullet combo I want and pick a 3g powder range I want to work in. Every round has a different charge weight step of 0.3g menaing no 2 rounds have the same powder charge. I find it a good early indicator as to weather a combo is going to work well and it also gives you an idea of velocity as well as lets you in on where the accuracy node might be in the charge weights i.e which charge weights were close together. Here are the results

 

 

this is 11 shots of reloader 7 starting at 20g going right up to 23g. I pushed it 2 grain over what quick load said was max with no pressure signs, I think it could maybe even go a touch further.

 

 

This is 11 shots of BL-C (2) starting at 25g going right to 28g, this is max published data though I think again I could go further as there were no pressure signs. If it hadnt a been for that flyer which was my own fault and the low one which was the lowest charge weight that group would have been 0.195 which is incrediable for 9 shots with a charge weight range of 3 grains.

 

My chorny was ballaxing about and as light was fading fast I didnt have time to mess around with it so I dont have velocity data but i reckon the top load of reloader 7 is doing close to 4000 fps and the BL-C2 load maybe 3800 fps, I have noticed that with all powders the 32g v-max has been most accurate at this velocity range my current pet load is 26g of h322 at 3900 fps, its a bit slow for this cartridge but you cant ignore that kind of accuracy its all that matters to me.

 

warm of group before I started the ladder test first 5 shot group of the day on a clean barrel with my H322 load

 

 

 

These as usual were all shot of a bipod and rear bag, I have been trying a few different rear bags latley and setteled on a caldwell leather/cordua mix, filled with red split lentils (thanks 6mmbr and pete01), I have started to realise how importanat a good fitting rear bag can be to repeatability.

 

I dont know if anyone really is too bothered about my tac20 and how it groups but I just post to keep the forum moving, somethign to do.