Lyman 49th ed gives 42.7-47.3 of RL19 with Sierra FMJBT, accuracy load is H4831 for 85 & 90gr bullets
Guys
I have been using 90 grain matchking with IMR 4320, it give very good groups but it is difficult to get hold of.
Reloader 19 should work in this calibre but I am havng problems finding load data. The only factory site I can find gives a load of 47 grains but other forums suggest 39 to 44 grains. Anyone got any experience using this powder for .243.
Lyman 49th ed gives 42.7-47.3 of RL19 with Sierra FMJBT, accuracy load is H4831 for 85 & 90gr bullets
Thanks pothunter
That gives me a start point to develop a load.
Do you have the velocities for the upper and lower loads
2922 - 3243, looks promising, might give it a try myself
"An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.
Thanks pothunter
I will let you know how it goes.
Randy I loked at that link but it makes no sense, the loads vary from 38 to 48 grains but all give approx the same velocity with the same bullet.
The reason is that the burn rates of the powders vary from RL15 ( the fastest) and RL22 the slowest. A fast burning powder will reach peak chamber pressure faster ( and fall off in pressure faster in the barrel) than a slow burning powder and so less of it can be burned in the chamber for the same peak. ~A slow burning powder reaches the same peak pressure but builds up to it and falls away from it slower so provides more net push for longer if you have the barrel length to use it.
Therefore there will be a sweet spot in terms of burn rate for every calibre/bullet combination that gives the most speed.
In this case it is RL17 because of the special chemistry of the powder and it's bulk density ( ie weight for volume). Slower powders will be slower as the bullet leaves the bore before as much "push" can be exerted on them and faster powders slower again because the are under the time/force graph will be less.
In all cases with alliant data min is 10% of max, start there and work up.
"An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.
Thanks Randy
I had not resd the data properly, what you wrote mskes sense thanks
"An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.
Yes Randy
I have been working on a target load, so far 36 grains of imr 4320 behind a 90 grain sierra matchking is giving very good groups but I have runout and so have the local dealers which was why I was asking about rl19 as I have a tub of it.
My rifle is a Howa 1500 with 20 inch varmint barel otherwise standard and it shoots sub 1 inch at 100 yds
Unusual to hear of someone using a .243 as a target round. Not so much from the perspective of the bore, the 6mm is certainly well-represented in the record books, but in terms of people who have gone for it over the PPC or similarly fashionable round. It's certainly the right sort of burn rate.
RL19 is the right sort of burn rate but I am told by some reloading friends I trust that RL 17 gives higher velocities for less pressure with the 90-100 grain bullets I plan to use. It can be a tricky powder to tune in just right however and in your shoes I would give the RL 19 a go first.
"An infinite number of monkeys banging away at type writers for an infinite period of time will eventually reproduce Hamlet" Thanks to discussion forums we now know this to be untrue.
I use RL17 behind my Berger 90gr in my Howa 1500 .243 I've had to reduce the speed of it to stay within the speed limit of bisley ( 1000m/s or 3280fps ) I'm running mine at 3250fps.
Vasbyt
Gas operative extraordinaire
What load of RL17 are you using??
Randy
I chose .243 for a number of reasons, it is a superb target round, the cases are very common, it is also a good hunting calibre. Also the actual guns are cheaper than 6mm and the performance is not that far behind 6mm.
When you have a gun capable of moa shooting it comes down to the person behind the gun, I have no interest in bench rest so bottom line reasonable cheap very accurate whats not to like about it