.243 Win what should I try next?

[taylorce1]

Take a look at the thumbnail (powder is I4350 not I3031):


Stevens 200 action
26" McGowen 1:7 twist Heavy Varmint Taper .243 Win
Kevin Rayhill Recoil Lug
Sharp Shooter Supply Competition Trigger

I know I'm going to have to bed the rifle, right now it is sitting in a Savage M12 Varmint synthetic stock. I was hoping to hold off the bedding job until I could get either a new B&C Medalist or McMillan stock for the rifle. But since the new stock is still a ways off, I'm going to have to bed the rifle if I want my groups to tighten up.

I'd like to bring my SD down as well hopefully into the single digits, do you think switching the primers would help with this? I haven't played with seating depth because I have the bullets out as long as I can get them while still feeding reliably from the magazine. Which still puts me a little over .030 off the lands.

I'm thinking of trying some H1000 or RL22 as well but I had 8 lbs of I4350 so I tried it first. I'd have to go buy the H1000 but have about 1.5 lbs of RL22 on the bench. Or should I just stick with I4350?

 

[mrawesome22]

My .243Win likes IMR7828 the best with 100gr bullets.

Might give it a try.

 

[GP100man]

Uncommon for the small bores but give IMR 4895 a go , I like the powder but not as much as the rifle did !!!

 

[Jim243]

I get good results with H-4895 and 105 grain Hornady A-Max.

Interesting a 1:7 twist 243 barrel, I haven't seen that before.

Jim

 

[hounddawg]

Target 2 shows potential, might want to mess with the COL a bit and see if it tightens up. I see a lot of horizontal stringing was the wind a kickin? also how many rounds down the tube? My .260 Criterion did not really get tight till I had about 100 rounds down it. A better or bedded stock will help for sure though. You can tweak the action screws also with your best group, set the front at 35 lbs/in the start at 10 on the rear and increase by 5 at a time. I have a Stevens action .204 in a Choate stock that will do 1/4 MOA at 35/15 but 35/10 or 35/20 it will barely do MOA

 

[GWS]

Try Winchester 760 ball powder. Extremely accurate in my short barrel Remington 600 using Sierra 100gr.

 

[PawPaw]

1:7 twist likes the heavy bullets best and you can shoot the long, low drag bullets in that barrel. I'd try the 107 Matchkings or the 115 DTAC with that twist. Personally, I like Reloder 22 in that caliber with 100 grain Hornadys and I'm getting better than 3100 fps with no pressure signs. My Savage has a 9 twist barrel, but if I had a 7 twist, I'd probably step up to the longer bullets. I've had some good short-range experience with the 105 A-Max, but I'm not sure if the bullet is fully stable. I'd like to shoot some paper out to 300 and look hard at the target to make sure that the bullet is not keyholing.

Use a slower powder and watch for pressure signs as you get close to the case capacity. There is a real good page at Accurate Shooter that should give you some starting points.

As soon as I get some other projects completed, I intend to get a 7 twist varmint barrel and see if I can't stretch out some of those heavier bullets.

 

[taylorce1]

1:7 twist likes the heavy bullets best and you can shoot the long, low drag bullets in that barrel. I'd try the 107 Match Kings or the 115 DTAC with that twist.

The targets on the spreadsheet were 107 SMK bullets. I've tried 105 A-Max as well, but it seems to like the 107's a little better. I'm just waiting to get more time together and try the 115 DTAC and Berger bullets, might even step up to the 120 Matrix bullets.

These are pretty average groups for the 107's so that is why I think I need to bed the rifle. Plus since my third group showed the least amount of standard deviation and was the smallest, I was thinking switching to a different primer might help decrease that SD into the single digits. I'd like to find a consistent load that would keep me in the 2800 fps +/- range.

I've been looking at different powders as well, I4350 was just what I had the most of. I have RL-22 on the bench so I thought I might try it or Retumbo at first since I had heard good things on velocity, but the more I researched these powders I found that they both could be very finicky and RL22 is more temp sensitive. I found a lot of guys who were having issues with Retumbo had switched to H1000 as it was more consistent of the two providing similar velocities.

 

[FrankenMauser]

I can't find it on the chart. What primer are you using?

My first impression of that chart.... use a different bullet.

My response after seeing that you may be willing to try a different powder... try Winchester Supreme 780.
It's a slow one (4831 class), but it works great. With your 26" barrel, I don't know why you're working with fast(er) powders, anyway. Just try 1 lb. I really doubt you'd regret it. You're already thinking about RL-22 and H1000. That makes W780 a walk in the park.


My personal experience with .243 Win and my own .243-based 6mm wildcat say stay away from H1000. The short/fat kernels of RL-22 and the other ball powder options will give better SDs. (I think it has to do with the massive surface area of the .243's shoulder, compared to neck diameter; in regards to powder kernels "following the bullet" into the throat/barrel.)


No matter what, you should bed that thing NOW, if you plan to do so any time soon.

 

[taylorce1]

I'm using CCI 200 primers because that is what I have the most of. I have CCI LRM, Remington 9-1/2, Winchester LR and some BR4 primers. I didn't use the BR4 because they are in APS strps and didn't want to take the time to get them out. I bought them during the primer shortage and don't have an APS priming tool.

I have a couple of pounds of H4831SSC I can try before I buy some 748 if there in the same class. I'll bed the rifle first chance I get but right now my new training schedule has me a little off and it is hard to find time to work on my rifles. Might just have to run it to the local smith and have him do the work.

 

[JMP]

I've been really happy with a somewhat hot load of RL-22 and 95 grain bullets in my .243. Almost gets boring its so consistent for me