2217 vs 2213SC which is a more consistent powder

[williada]

Bad_primer these slow burning burning powders like pressure to burn efficiently. There are a couple of options at either end of the spectrum and particularly if the weather is cool. Firstly if you seat the bullet deeper, you can increase the bullet compression of the powder and so increase pressure. The increase in velocity may also take out the vertical you see on the target. On the other hand, VLD's have traditionally been jammed into the lands, but importantly it creates pressure if the case is not full to fully burn the powder so most likely it will reduce ES. It is a folly to enter a long range shoot without doing a proper seating depth test to draw scientific conclusions as to the suitability of the powder. Note that there is a point that jamming does not necessarily increase velocity but it does increase pressure. Watch for over pressure at all times.

[bad_primer]

Bad_primer these slow burning burning powders like pressure to burn efficiently. There are a couple of options at either end of the spectrum and particularly if the weather is cool. Firstly if you seat the bullet deeper, you can increase the bullet compression of the powder and so increase pressure. The increase in velocity may also take out the vertical you see on the target. On the other hand, VLD's have traditionally been jammed into the lands, but importantly it creates pressure if the case is not full to fully burn the powder so most likely it will reduce ES. It is a folly to enter a long range shoot without doing a proper seating depth test to draw scientific conclusions as to the suitability of the powder. Note that there is a point that jamming does not necessarily increase velocity but it does increase pressure. Watch for over pressure at all times.

That’s awesome advice, thanks you! I’ll trialing them again at the next 600M shoot.

[bruce moulds]

bad primer,
seating bullets on the lands or within a few 0.001 is fraught with danger for both grouping and s.d. generally but not necessarily.
0.010+ jump or jam would be a minimum starting point.
assuming powder burning rate is such that full potential ballistics cannot be achieved in that case capacity, do not be too concerned by compressing.
as you continue to compress, pressures do not seem to climb any faster than adding powder in an uncompressed load.
just look for pressure signs as would normally.
your target could be an s.d. report, poor grouping, or a combination of both.
any powder needs 2 things for accuracy, consistent ignition and consistent burn.
interestingly, federal makes a 215 gold medal primer which might help, or you might need a cooler primer.
some of ignition comes from the primer, and the rest happens as pressure rises, causing heat to rise, becoming a vicious circle until all that can burn is alight.
do you need a hotter primer to ignite compressed powder? who knows.
certainly your s.d. needs to be brought down significantly.
rather than just trying things at a normal shoot, you might need to spend a day at the range testing in a more thorough and organised manner.
bruce.

[Ian Hughes]

Hi all
I run a pair of 280ai rifles in NZ. As many of you are aware we have an energy limit of 4500J on our Trentham range, so for a 180gr bullet this limits muzzle velocity to 2881fps. both rifles have Kreiger 5R 8.5 twist barrels at 31". I used 2213 for a couple of seasons and found it to be reasonably accurate, but at the pressures generated to run at a velocity of 2840 to 2850 i was getting a carbon build up just past the throat. It was suggested to me by a fellow shooter to try 2217, this at the same speed did not affect accuracy, but the main difference was 2217 burnt a lot cleaner. A couple of weeks ago i put both rifles on the Labradar and one rifle measured an SD of just under 7 and the other just over 7 with the same load. the other thing i have noticed is that 2217 does not appear to be affected by temperature as much as 2213.My loads for these velocities were for 2213 56gr and for 2217 57.6gr. Is this of any help?