.243 win question

[Bud6mm]

I am loading 105 amax. The load is
.010 off the lands
41.5 grns h4831sc
Cci 200 primers.
Model 700 sps varmint factory barrel
My dope leads me to believe I'm running right around 2700 and I was wondering what I could do to get more speed. I want a flatter trajectory because it is a little more forgiving for a new guy like myself. I only have h4831sc and IMR 4350 on hand. I am not against getting more variety, but I am having a hard time figuring where to start. Also could there be another node with a larger charge above 43 grns. My groups went from 1/2-5/8 with 41.5 to about 1.5" with 43grns. Any help would be great. Thanks in advance.

 

[diverdon]

I'm just about to get started with the .243 myself. I just wonder if you have not tried a powder that gives faster velocities? Take Aim at Rifle Reloading Data | Hodgdon Reloading
Lists max loads: 49.0C Retumbo 2986fps, 47.0 Supreme 780 3036fps and other loads that seem at least 200fps faster than you are claiming.

 

[Shootinsurveyor]

When i researched loads for my 243, i found that alot were using H4350. Im getting 2925fps with 39gr of it. Its a fairly mild load compared to alot that are out there, but it does get the speed you were looking for.

 

[6brshooter]

I run 43.0-44.5 gr of h4831sc with 105 berger &107 smk. I get velocities of 2950-3080 in a 24",26", and 28". With imr4350 i use about 42.5 gr with a 107 smk in a 25.5" and get 3090@95* &3020@50*. I also run 41.8 gr h4350 with 105 bergers in a 24"@3130fps. I ran low on h4350 last summer so found some substitute loads using imr4350 and h4831sc. I like the temp stability of the h powders over imr. I also prefer the slower h4831sc in 26"+ barrel lengths. Powders slower then h4831sc burn rate are just going to disappoint u speed wise. I'm actually surprised that ur getting 105s to stabilize at low velocities in that 9 1/8 twist barrel.

 

[TOP PREDATOR]

when i went to .243 year or two ago, i heard the term a "barrel burner"

from what i've gathered doing research to develop a load (even before i bought the rifle), the quicker / hotter burning powders create throat erosion and other wear at around 2,000 rounds. i don't know this to be fact, just passing along what has been passed along by a majority. so i went with a slower, "cooler" powder that supposedly is kinder to the throat / barrel, H-1000. a pound gets me 150 rounds

my rem 700 varmint 26"

105 amax 2.780oal 46.5 gr 2850fps -.015 off the lands

105 bthp, same data but at 2.780 is -.005 off the lands

i found 100 btsp at 47 gr 2.698 (-.010 off the lands) 2900 fps are nominal difference between the three out to 420Y (my longest local range) with drop / POI / POA being the same. JBM confirming the same, it appears the more premium bullets pay off past 550Y. average groups 3.5" or less CTC at 420Y

i can't speak of the barrel burning / throat erosion as of yet, i have about 550 rounds through it.

through all the research i did do, I'd have to say that most are going with the H4350 & H4831, but there are a whole bunch of powders that are being used in the .243, there is a seperate .243 load thread that lists a ton of them.

 

[6brshooter]

My 24" remage just bit the dust, well it was still shooting1/2-3/4 moa but it had lost about 100 or so fps. It did shoot pretty regularly in the .2-.3s. Rd count was 2500ish of 107 or 105@ 3090-3130. It got fed a steady diet of h4350. Yeah it isn't friendly to barrels, compared to 308, but who wants to pull two sparkplug wires off a V8 so it gets V6 fuel mileage? Pressure =velocity=shorter barrel life, no free rides.

 

[Flather18]

You might try H414 (Win 760). I have had great result with that. I have also heard Vihtavuori 540 is great for 243 as well

 

[Sixfivesavage]

44.1 grains of H4831sc gets me what I figure to be about 3050 fps from my 26" 243ai as a forming load with berger 105s. Have you seen pressure yet? Maybe continue to work up some?

 

[TOP PREDATOR]

but who wants to pull two sparkplug wires off a V8 so it gets V6 fuel mileage? Pressure =velocity=shorter barrel life, no free rides.

i wish i came up with that

 

[Geno C.]

i wish i came up with that

How about, barrels are like tires. You can take it easy on them and they will last a bit longer but that's not much fun either

 

[2Shots]

I just put a fresh barrel on my 243 after shooting out the previous in 1000 rds with H4350 and 115's. Shooting 105's now with H4831Sc, 45.5 gr will get you 3150fps and some more on occasions, settled on 44.0 running about 3050. Tried h1000 early on but couldn't get any speeds, had to run a faster burn rate.

 

[aagifford]

I'm using 44.5 gr h4831sc with sierra 107's. Getting 3000 fps on a 28 in barrel. Got 2330 rounds through it right now. Still shoots ok, around .38 moa or so.

 

[pawprint2]

I am loading 105 amax. The load is
.010 off the lands
41.5 grns h4831sc
Cci 200 primers.
Model 700 sps varmint factory barrel
My dope leads me to believe I'm running right around 2700 and I was wondering what I could do to get more speed. I want a flatter trajectory because it is a little more forgiving for a new guy like myself. I only have h4831sc and IMR 4350 on hand. I am not against getting more variety, but I am having a hard time figuring where to start. Also could there be another node with a larger charge above 43 grns. My groups went from 1/2-5/8 with 41.5 to about 1.5" with 43grns. Any help would be great. Thanks in advance.

When you switch back to 41.5 does your accuracy return? If not, you have another problem, barrel (maybe just a good cleaning), scope/mount. If it does, you've found a great load for your rifle, take it back to 41.5. If you're dead set on 43.0grains, do a primer test, same load, 3 or 4 various primers, you'll be amazed at the differences between groups (most of the time). Good luck.