Just starting on my 1st 223 turnbolt rifle. "Off the shelf" Remington 700 SPS Varmint with 26" barrel and 8" twist. Put in a Rifle Basix trigger. Will be doing a ladder test with CFE223 & 80gr SMKs. With my ARs I have found the 80gr SMKs shoot best when just jammed (<0.005"). What are folks doing with 80gr SMKs in bolt-guns? I'll start my ladder at 24gr of CFE223 (unless someone out there wants to send me some RL15 or Varget), going up by 0.1gr. But, am wondering about length?
1st 223 Turnbolt Loads w/80gr SMKs
- Thread starter AR Shooter
- Start date
Texas Solo
B.S. High Master
I would not jam a SMK. It's a tangent ogive, and they always seem to shoot better when jumped .020 - .030
Also going up by only 0.1gr is a waste of bullets & powder. Most nodes are up to .03gr or more, so go up .03gr at a time and then refine if you want once you find what shoots best.
Also going up by only 0.1gr is a waste of bullets & powder. Most nodes are up to .03gr or more, so go up .03gr at a time and then refine if you want once you find what shoots best.
I have also had the best luck by just barely touching the 80 SMK. Went around the ogive with a dry erase and kept seating it back until it had very slight rifling marks.
Charge is largely dependent on your throat length. What COAL will you be loading to?
* I would also add, just because a bullet has a tangent ogive doesn't necessarily mean it won't like being jammed/touched. It will likely be easier to tune as far as seating depth than scecant ogive bullets though.
Charge is largely dependent on your throat length. What COAL will you be loading to?
* I would also add, just because a bullet has a tangent ogive doesn't necessarily mean it won't like being jammed/touched. It will likely be easier to tune as far as seating depth than scecant ogive bullets though.
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Ned Ludd
Silver $$ Contributor
Hodgdon currently has one pounders of Varget: https://shop.hodgdon.com/hodgdon-varget/
If you plan on single feeding and your chamber allows, I would start the 80s at ~.015" off "touching", whatever CBTO measurement that may be. Once you have optimized charge weight, I would start by testing seating depth from "touching" to about .030" off in .003" increments. Note that the starting seating depth of .015" off is in the center of that range. Thus, you're only moving the bullet half the total seating depth range in either direction after charge weight testing, which is not far enough in my hands to require an additional visit to charge weight testing due to potentially altering the effective case volume. Only if you do not find anything satisfactory by this approach would I move on to testing the bullet jammed.
If you will be constrained to mag length, find the longest CBTO that will feed reliably and start there. Once charge weight is optimized, test seating depth in .003" increments moving the bullet only in the direction of farther off the lands, as far as you need to go to find the sweet spot. If you have to seat the bullet far enough from the lands, it may require an adjustment of charge weight because the effective case volume will decrease as the loaded rounds becomes shorter (COL).
Loaded up 15rds at 0.010" off with 24-25gr of CFE223 in 0.1gr increments. Did not show a node at 200yd. The 5rds at 24.5gr shot a sub-1" group, so seems a good place to start. Think my biggest problem is I'm using LC cases from my AR while waiting for the Lapua cases to arrive. At that point I'll have to start again. The good news is I'm not seeing anything I would call pressure-signs at 26gr. Once the Lapua cases arrive I'll break out the chrony, as well.
Thanks for the feedback.
Thanks for the feedback.
jelenko
Gold $$ Contributor
LC cases are not the limiting factor to groups less than 1 MOA.
There are many AR shooters using LC brass and getting 1/2 - 3/4 MOA.
What Jelenko said. I use once-fired LC in my LR Palma rifle. It's well under 1 MOA when I point it there. It's all I've ever used for service rifle. When it didn't land in the x-ring, it's my fault. LC vs. Lapua brass is waaay down the list of critical factors in .223 accuracy, in my opinion.
The new 700 Alpha 1 has a 1:8 twist.
Yes. SPS Varmint. Did put in a Rifle Basix trigger.
Reference to the LC cases is that they are a bit beat up from being fed thru an AR action, not that there is anything wrong with them other than that. Have cleaned up 100 and will anneal them and be ready for action. They will be fine once fire-formed. Might even weigh-sort them.
The 80gr SMKs shot well, so next up are 80gr Berger VLD and 80gr Nosler. Shoot em if you got em.
Have a Boyd's stock inbound, which will add some additional weight.
This just to have an action where the 7" twist Bartlein barrel I've got on the shelf will reside.
All in good fun.
Hell must of finally froze over.
OK. Have 30rds down the tube and did a bit more testing at 300yd this a.m. Was in a bit of a hurry so only put 3rds, each, with 24.5gr of CFE223 pushing an 80gr SMK, 80gr VLD and an 80gr Nosler. The one Nosler flyer was from a round I dropped on the floor that bent the tip a bit. The SMK & VLD were both under 1" and think the Nosler would be there as well if I had three good rounds. Pretty decent results from a stock Remington 26" SPS Varmint barrel with an 8" twist. I'll shoot a relay (20rds) with each load at Sunday's 600yd F-Class match and see which one holds up the best.
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The 80gr VLDs shot a 185-4X, 80gr SMKs were an 180-2X and 80gr Nosler were 173-2X.
Quite pleased for the 1st time out with the rifle. Next time will be with a proper Nightforce scope and a tweaked trigger.
Will do some 'jump' testing with the VLDs & SMKs as well. Will leave the Noslers on the shelf for now.
Quite pleased for the 1st time out with the rifle. Next time will be with a proper Nightforce scope and a tweaked trigger.
Will do some 'jump' testing with the VLDs & SMKs as well. Will leave the Noslers on the shelf for now.
Try jamming them .010 to .020 in. Always the seating depth to beat in my rifles!
Paul
10XSHOOTER
Gold $$ Contributor
Even the new 700's not Alpha's in .223 have a 1-8 twist from the factory
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