Those Berger's touch the rifling at about 2.835" coal and the load I came up with 4064 was .025" off. Tried an ocw with some varget today at the same .025" off. I'll post target when I get home in a bit.
Expected accuracy of featherweight contour
- Thread starter markg208
- Start date
Help Support Long Range Hunting Forum
@markg208 maybe it's me but I see your load development differently. First, though, what are you using to measure your charge weight? Have you cleaned the carbon out since you started load development? What scope are you using? What's your setup for how you are shooting groups (prone w/ bipod/rear bag, bench w/ bipod/ rear bag etc)? Where do you live and what are the temps? Are you in the south w/ high temps, humidity, mirage even in the winter?
Here is where I would search from your previous pics.
First, that group is under an inch. It's actually 2/3 MOA.
Second, shoot a couple more 3 shot groups at 43.7, 43.9, 44.1 and see what things look like. The ES between 43.5 and 44.3 is 48fps…that's 6 shots over 0.8gr of powder. That's not too bad.
Even though you only shot 3 rounds at 43.9 it had an ES of 16 and it's a nice round group. 43.5 had more vertical and 44.3 was almost pure horizontal. A rifle that shoots 2/3 MOA w/ an ES of <20fps will do really well out to as far as that cartridge (.308 Win) and that bullet are capable.
That said, if you can get some Varget, N540, or IMR Enduron 4166 they would be worth trying for sure.
Here is where I would search from your previous pics.
First, that group is under an inch. It's actually 2/3 MOA.
Second, shoot a couple more 3 shot groups at 43.7, 43.9, 44.1 and see what things look like. The ES between 43.5 and 44.3 is 48fps…that's 6 shots over 0.8gr of powder. That's not too bad.
Even though you only shot 3 rounds at 43.9 it had an ES of 16 and it's a nice round group. 43.5 had more vertical and 44.3 was almost pure horizontal. A rifle that shoots 2/3 MOA w/ an ES of <20fps will do really well out to as far as that cartridge (.308 Win) and that bullet are capable.
That said, if you can get some Varget, N540, or IMR Enduron 4166 they would be worth trying for sure.
The Oregonian
Well-Known Member
I see this as his most recent post (post #30 above) 5, 6, and 7 all print in the same area, which is the goal of OCW (good groups that print in the same area from charge to charge). There is one of the shots in group 6 that takes that to a 1" group, but I would check that node with seating depth. That's 44.0 to 44.8 grains printing in the same area…that's where I would start as well.
Last edited:
Great information
But I'm a little bit confused
How did you use a brass screw and lapping compound to polish the crown
Was the screw actually used as a tool to hold the lapping compound
My son works at a race shop building race car engine and he uses a hand tool to hand polish valves in a cylinder head
So is that about the same kind a of tool
But I'm a little bit confused
How did you use a brass screw and lapping compound to polish the crown
Was the screw actually used as a tool to hold the lapping compound
My son works at a race shop building race car engine and he uses a hand tool to hand polish valves in a cylinder head
So is that about the same kind a of tool
I see it as 43.5-44.8 printing in a similar area at 100 yards…which brings up another point I'll talk about in a second.
In his latest OCW test the 44.8gr group is .48 MOA. In his previous test, 43.9 was .66 MOA. The ES of his 3 shot group at 44.8 is 25 whereas at 43.9 it was 16. While 3 shot samples are small. The ES at 43.9 is nearly half of what it was at 44.8. That shows up at distance. The ES between powder charges on both sides of 44.8 is 63fps. At 43.9 it was 48fps. Which makes me think that it's not as stable at the higher end of the node.
Which brings me back to 100 yards…If possible you should do your load development at 300 yards, or if there's no wind, 500 yards. Groups at 100 don't mean much. In your instance you have 2 loads that are ~1/2 MOA at 100. I bet they shoot completely differently at 300 and beyond. With what you have presented thus far, I would load up 3 of 43.7, 43.9, 44.1 and 3 of 44.6, 44.8, and 45 and shoot them at 300 or 500 (if no wind). You'll see what I am talking about. Tightest group wins.
In his latest OCW test the 44.8gr group is .48 MOA. In his previous test, 43.9 was .66 MOA. The ES of his 3 shot group at 44.8 is 25 whereas at 43.9 it was 16. While 3 shot samples are small. The ES at 43.9 is nearly half of what it was at 44.8. That shows up at distance. The ES between powder charges on both sides of 44.8 is 63fps. At 43.9 it was 48fps. Which makes me think that it's not as stable at the higher end of the node.
Which brings me back to 100 yards…If possible you should do your load development at 300 yards, or if there's no wind, 500 yards. Groups at 100 don't mean much. In your instance you have 2 loads that are ~1/2 MOA at 100. I bet they shoot completely differently at 300 and beyond. With what you have presented thus far, I would load up 3 of 43.7, 43.9, 44.1 and 3 of 44.6, 44.8, and 45 and shoot them at 300 or 500 (if no wind). You'll see what I am talking about. Tightest group wins.
ridgewalker
Well-Known Member
Spindly barrels can be very finicky. But remember first cold bore shot is the only one that counts in a hunting situation. Under 1 MOA is plenty good to over 300 yards even down to coyote. IMO&E
Handsome little rifle!
Handsome little rifle!
I run Varget and the 168 Amax or ELDX with great results. 1/2 MOA out of a light sporterweight 308. Think I'm at 44.5 of Varget with CCI LRP's.
Slow down, reloading for accuracy is not a race. Take your time and synthesize the recommendations being presented to you.
rustyshackleford
Well-Known Member
You should be able to get sub MOA accuracy. My factory M70 EW in 30-06, which I'm told is an inefficient and inaccurate design, will group under an inch for 3 shots very easily with kibble it likes.
CNY Yote Hunter
Well-Known Member
Looking at your targets I see a similar issue I just had a thread about that I'd be interesting in seeing your results. It looks like almost all of your groups have 2 shots relatively close to one another and one flyer. Do you mag feed when shooting these groups or was it done single fed? I'm interested to know because I found with a 17 hornet that when I was mag feeding I had 2 issues going on, one I can prove and the other not so much yet other than field results. I found the projectile was getting pushed back into the case upon loading but not every time throwing my cbto off. On top of that I had asked if anyone had ever seen a bolt gun shoot different from the pressure of a round in the mag up against the bolt, obviously 2 rounds in the mag would equal greater pressure on the spring resulting in more force upwards on the bolt and pressures/ harmonics are everything with results for groups. Could you do a test single feeding the rifle with no mag and then one with the mag and see if that helps?
lancetkenyon
Well-Known Member
Nice looking rifle.
Here are my suggestions/comments.
You spent about 300-320 more rounds than I would have with your first powder/projectile choices. If I don't get some semblance of desired accuracy in the first 30-50 rounds, I move on.
Try shooting all cold bore shots. I have loaded a few pencil barreled rifles, and 3 cold bore shots (at least 15 minutes between shots) would all go into .25" +/-. Two in a row would be .5", every time. And three in a row would go 1"+ groups.
What is the intended use of this rifle? I assume, since it is built so light, hunting was the main goal? I would look at a Sierra Match King or Game King, Berger, or even a lighter mono like a Hammer Hunter. Not all guns like all bullets. But with a custom barrel, it should be shooting better.
Here are my suggestions/comments.
You spent about 300-320 more rounds than I would have with your first powder/projectile choices. If I don't get some semblance of desired accuracy in the first 30-50 rounds, I move on.
Try shooting all cold bore shots. I have loaded a few pencil barreled rifles, and 3 cold bore shots (at least 15 minutes between shots) would all go into .25" +/-. Two in a row would be .5", every time. And three in a row would go 1"+ groups.
What is the intended use of this rifle? I assume, since it is built so light, hunting was the main goal? I would look at a Sierra Match King or Game King, Berger, or even a lighter mono like a Hammer Hunter. Not all guns like all bullets. But with a custom barrel, it should be shooting better.
George Koch
Active Member
I had a brand new 300 once it didn't like any powder or bullet combination. After a lot of checking apparently my barrel must have been the last one used on a reamer that had been used on a 1000 other barrels. (Lol) the chamber was in foul shape. I had it cut back and rechambered. It was still a little particular finally found a powder and a sweet spot with some Bergers and she would cut or touch the same hole at 300 yards.
Lesson learned just because you can't see a lot with mere eyesight and just because it's brand new sure doesn't mean it's perfect or up to par
Lenny Foffa
Well-Known Member
- Joined
- Mar 6, 2017
- Messages
- 1,544
My. Go to deer. Rifle is a. Weatherby Ultralight rifle. 24. Inch. Krieger flutted S/S barrel,in270. Win! Thin barrel ,550 at the. Muzzle'
10. Or 12. Years ago. I could. Make. One. Hole. Groups at 100. Yards if I. Let the. Barrel. Cool! Now. At 73. I'm. Happy. With 1 And1/4. Groups! I. Learned. Shot. 1.and shot 2. Are. Usually. Fine but. I. Give the. Barrel 1 min. And 15. Seconds. Fir. Shot. 3. And. 1 min snd 40 seconds for all. Shots after. That ! I. Must. Say. Most of my deer are. Shot snd. Killed. With. The. First shot. ,two needed a. Second shot ,never. Fired. A. Third shot ! For Me. Light weight. Thin barrel , let it. Cool
10. Or 12. Years ago. I could. Make. One. Hole. Groups at 100. Yards if I. Let the. Barrel. Cool! Now. At 73. I'm. Happy. With 1 And1/4. Groups! I. Learned. Shot. 1.and shot 2. Are. Usually. Fine but. I. Give the. Barrel 1 min. And 15. Seconds. Fir. Shot. 3. And. 1 min snd 40 seconds for all. Shots after. That ! I. Must. Say. Most of my deer are. Shot snd. Killed. With. The. First shot. ,two needed a. Second shot ,never. Fired. A. Third shot ! For Me. Light weight. Thin barrel , let it. Cool
