Deer Hunting Loads for .243 Win...Need Advice

[WVGearhead]

I am trying to work up a deer hunting load for two .243 Wins in the inventory with less than satisfactory results so far. Using Hornady 100 grain Interlock BTSP with a variety of powders (IMR 4350, 4064, and 4831; and Ramshot Big Game). So far, I haven't been able to get anything to reliably group.

Rifle 1 - Winchester Model 70, 20" barrel, 1 in 8" twist (I think)
Rifle 2 - Remington Model 700, 22" barrel, 1 in 9" twist (I think)

Any recommendations on a bullet/powder combination you have had luck with?

 

[horsemen61]

I use that bullet and 42 grains of H 4831

use at your own risk of course

ymmv

 

[Hog huntin Harry]

.

 

[Hog huntin Harry]

Here's some .243 Winchester loads from "Game Loads And Practical Ballistics For The American Hunter" By Bob Hagel

 

[AJC1]

May want to try ramshot hunter vs big game. In that size case I use a lot of varget and ar comp.

 

[stillquietvoice]

What coal are you using? It's likely that you will need 2 different loads, one for each rifle. I'm on my second 243 win the first was well used when I acquired it. It's throat was eroded, had to load longer, 2.700", but it shot. 75" groups with several powders, imr 4895, h 4895, imr 4350 and win 760. It so happened that particular gun liked Max charges of each of the above mentioned powders.

My new one has shown promise with ramshot hunter, h4350, and imr 4350. With hunter 42.1 - 42.2 at 2.67" has given one hole groups, h4350 39.8 gr, and imr 4350 40.0 gr same length and same bullet you are shooting as well as Sierra 100 gr gameking.

Biggest problem with multiple rifles is that each one is different and may like different bullets, powder, charge wt and coal's.

Do you know the length to the lands in each rifle?

Ramshot hunter is in the 4831 burn rate

 

[AJC1]

Ramshot hunter is in the 4831 burn rate

 

[WVGearhead]

@stillquietvoice, I have been loading COAL to the Hornady book spec, which is 2.630. I don’t know length to lands. How far off the lands are you seating?

 

[AJC1]

@stillquietvoice, I have been loading COAL to the Hornsby book spec, which is 2.630. I don’t know length to lands. How far off the lands are you seating?

Starting coal for accuracy normally starts at 20k.

 

[stillquietvoice]

sorry thought I saw it listed on a burn rate chart close to 4831.

.020 off the lands.

 

[stillquietvoice]

Most load data I've seen show a 2.650 as a coal. Iirc Berger all copper require a longer jump for best accuracy. .040-.050 jump. I could be mistaken on manufacurer though.

 

[AJC1]

Most load data I've seen show a 2.650 as a coal. Iirc Berger all copper require a longer jump for best accuracy. .040-.050 jump. I could be mistaken on manufacurer though.

All solids are recomend to start 50k off. Barnes makes a few.

 

[stillquietvoice]

Thanks couldn't think of wich company I tend not to use copper solids.

 

[AJC1]

Thanks couldn't think of wich company I tend not to use copper solids.

The only reason I know anything about solids is California being stupid as normal was trying to ban all lead bullets not just hunting. I would be so screwed. I would never shoot a solid in my war trophy 7.7

 

[WVGearhead]

Thanks for the feedback, all! I think my next step will be to figure out OAL for both, seat 0.020 back, and go from there. The mod 700 belonged to my Father-in-law and my youngest wants to hunt with it. The mod 70 was my first rifle. Both have a bunch of sentimental value and I want to see them shooting well.

 

[243winxb]

Find a shorter bullet. Run the calculator. https://www.jbmballistics.com/ballistics/lengths/lengths.shtml

A Sierra 85 gr hpbt #1530 with Imr 4350 should group 1.25" or better @100 yards. COL 2.660"

 

[Arkansas Paul]

I took the Ruger M77 .243 to the range today and had good accuracy with that exact same bullet and 41 grains of IMR4350.
Decent results with Varget, but better with the slower powder.

 

[AJC1]

Thanks for the feedback, all! I think my next step will be to figure out OAL for both, seat 0.020 back, and go from there. The mod 700 belonged to my Father-in-law and my youngest wants to hunt with it. The mod 70 was my first rifle. Both have a bunch of sentimental value and I want to see them shooting well.

If you have not seen the burger seating depth test it's a great way to get dialed in quickly

 

[WVGearhead]

@243winxb out of curiosity, what is the rationale for the shorter bullet?

 

[AJC1]

@243winxb out of curiosity, what is the rationale for the shorter bullet?

It's a stability calculator that shows if you have enough twist. Unstable bullets are not as accurate and dont have as good of bc

 

[243winxb]

out of curiosity, what is the rationale for the shorter bullet?

Calculate a stability factor for a bullet using the Miller stability formula. Output is red for unstable, yellow for marginal stability and green for stable. https://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi

A shorter bullet works better with slow twists like 10.

Short barrels produce less velocity & slower bullet RPM. A faster twist is needed or higher velocity for bullet stability.

 

[243winxb]

Rifle 1 - Winchester Model 70, 20" barrel, 1 in 8" twist (I think

Factory barrel? Should be closer to 10 twist?

Berger calculator-

 

[BBarn]

As suggested, try shorter bullets. The 700 is probably 9.125 twist, the 70 10 twist. Some 700s might stabilize a 100 gr boattail, but less likely in the 70.

My 9 twist won't stabilize 105gr boattails, 8+" groups. Does much better with 100gr boat tails. A small change in bullet length can make a big difference.

 

[WVGearhead]

@243winxb thanks for the information. Both are factory barrels, but having a hard time determining twist. The 70 was bought new in the late '80's. It is a featherweight carbine model. No idea on when the 700 was produced, but I am guessing '70's. The research I have done suggests that @BBarn is correct on the twist for the 700. I got on the calculator and can see the difference bullet length makes now. Thanks!

 

[horsey300]

@243winxb thanks for the information. Both are factory barrels, but having a hard time determining twist. The 70 was bought new in the late '80's. It is a featherweight carbine model. No idea on when the 700 was produced, but I am guessing '70's. The research I have done suggests that @BBarn is correct on the twist for the 700. I got on the calculator and can see the difference bullet length makes now. Thanks!

Model 70 has a 1:10 look hard at 95 gr sst and 100 gr prohunters
700 has a 1:9.125, run everything from 55-103 through it I like stuff like the interlock or gameking 100 gr, 90 gr tgk, and 103 eld. Getting just under 1.5 moa with the tgk, will try the 103 when we run out of the tgk. If it won't shoot with a prohunter/sst (they're both flat based) then clean it good, try again, and if still no luck, call a smith. Powders I like are staball, 4451, and h1000, the 4350 is VERY close to 4451 iirc, would be a good place to start with what you have on hand. I loaded my rem from 2.62-2.68 and found no issues (dependent on ogive and distance to lands and type of bullet of course). Good luck! Looking forward to the results!