2016 223 Build

[jsthntn247]

Re-barreled my 223 to a custom contour 6.5 twist Bartlein with a Ezell PDT tuner on it. Went a little heavy on the contour so I had to swap rings and bases out to some lighter ones to get it back under weight. I also got it throated out longer than the last barrel but don't think I went long enough, would go .210-.220 on the freebore if I had it to do all over again. It's showing some promise but for some reason (never had a problem before) I can't seem to get my best groups and ES to coincide together. I've tried several different primers and the ones that give acceptable velocity spreads don't shoot as good. I'm taking it to the first match this weekend and will try two strings with one primer that shoots best but a high ES against the other primer that doesn't shoot quite as tight but has an ES around 10 and see what happens. The joys and frustrations of a small case and big bullet.

 

[mac86951]

Which bullet?

 

[skiutah02]

I'll be following this one with interest. Based upon past conversations, I'm guessing he's in the 90vld game....Drew

I'm thinking about 200FB. That's why I'll be following this thread.

 

[MrMajestic]

PTG throater will fix that right up. Nice rig!

 

[mac86951]

I'll be following this one with interest. Based upon past conversations, I'm guessing he's in the 90vld game....Drew

I'm thinking about 200FB. That's why I'll be following this thread.

I'd assume the same. My guess on ES vs accuracy is going to be a seating depth vs. neck tension question. Aside from bullet, next question is going to involve brass handling/COL. I see mentioned that previous barrels weren't an issue, round count on this barrel is another to question to ponder (is it broken in yet?). ES vs. accuracy node comparison between barrels is very tricky to get an apples to apples evaluation. Even the smallest chamber cut differences can result in drastic differences. In my experience, 3 of 3 custom barrels cut by the same reamer, still had small load variations to find accurate nodes. That said, accuracy was where I expected them to be, which also had good ES.

What range are you comparing accuracy at? the 90vld at 1:6.5 twist I've seen take more than 100y to 'settle' unlike lighter bullet weight/twist combos.

Off-hand assuming 90gr, if accuracy is being measured at 100y for comparison to older barrels, I'd say go longer and see if accuracy and ES better correspond, followed by a prescribed additional round count and re-evaluate to see if the phenomenon shifts with more shots through the barrel. Also, of observation I see a tuner on your barrel, what is your load-work up process? Are you comparing accuracy after setting tuner for each load?

-Mac

 

[jsthntn247]

I test for powder charge, then seating depth, then neck tension, then adjust the tuner. I'm actually jumping these 12 thou where the last barrel wouldn't shoot jumping. I agree with round count possibly being a factor, it's got 172 on it now. The tuner really sucked the groups up. I was getting 1/3 moa after testing with the tuner bottomed out on 29. I started backing it off 2 increments at a time with 5 shot groups at each. From settings 25 to 21 it would shoot as tight as I could hold then opened back up at 19.

 

[Dusty Stevens]

Would you really go with a good chronograph load over one thats good on paper? They score the paper.

 

[jsthntn247]

At longer distance, it will show up. Me and the conditions generally cause enough vertical issues in a match, don't need the load adding to that. The other primers still shoot under 1/2" just not one hole. Hopefully the wind wont be terrible and I will be able to get a reasonable idea on which shot the best on Saturday.

 

[jsthntn247]

Posting this to help others. Shot this today to get a zero for the match. First shot was low left, adjusted the scope and shot 7. The last shot blew the group but the first 6 just over 1/4" outside to outside. My es was 41 fps. I will try and take pics of a target shot tomorrow to post what the vertical looks like at 600.

 

[skiutah02]

Nice.

 

[expiper]

I would throat it to where there is ~.125 of bullet shank in the case to increase case capacity and still have room for erosion,,,what powder are you using??? Rx-15-16-17 ??....I prefer the 223 over the 308 because of my recoil sensitivity,,,(gettin old)...Roger

 

[jsthntn247]

If it does not shoot well, I'm going to leave it with the smith and have him throat it out another .030 This load is slightly compressed and could be the reason I'm having a problem with ES. When its compressed my hydro seating die is useless so it might not actually be from the compression and more from neck tension differences that I can't see due to the powder compressing.

 

[jsthntn247]

H4350. I'm trying to run the low 2650 node. I dont think it's necessary to run the higher nodes for mid range. I want to see if the slower powder at lower pressures will greatly increase brass and barrel life. Any idea what the pressure would be at 2.670 COL 25.7 gr of 4350? Last barrel ran the same speed with .5gr less powder without compression.

 

[jsthntn247]

Got second in the match and never shot on a clean target to take a pic. It was very tough conditions to evaluate a load. Gun shot well enough to win but I blew the last string by getting impatient and not waiting on favorable conditions to come back. I could see a little more vertical than I like in the first string when the winds weren't horrible. If I had enough 90's left I would try and work a load up with Varget to see if I could get the ES lower.