Ex if you shot them all with no wait then wait a until the gun cools down or viceversa.
- This would be my next suggestion. Barrel heat can easily cause groups to open up, especially in a factory barrel. The factories don't go to the expense of stress relieving their barrels; most aftermarket barrel makers do. The button rifling process introduces significant stress into the steel, and as the barrel heats up from shooting, this stress can cause the point of impact to shift slightly. To help identify if this is your problem, try shooting a group your normal way, then let it cool thoroughly. Then shoot another group using the same ammo, except this time let the barrel cool completely between shots. If your range has power, bring an electric fan with you to help speed this up. If barrel stress is a factor, this will reveal it. I have two factory sporter rifles, a Weatherby 7-mag and a Browning .243, that refuse to group well warm. If I do as I explained above, both shoot about an inch.
Realize too that 1/2" or slightly under, as you stated, for five shots, is pretty darn good for any factory barrel. It's possible that there's not much more to be gained here without going the custom barrel route.
What kind of loads were you using with the 155s?
I've been using 155s for about 4 years now, with *no* issues.
This is from load testing earlier this year (February) on a nice clear, crisp morning with no mirage, and basically zero wind (great day for load testing!):
(sorry for the fuzzy pic, I went downstairs and snapped a cell-phone pic of the target)
Like I said, the barrel on the 12 F/TR tend to shoot 155s very, very well in my experience (I'm on barrel #5).
I am loading up the 175s tonight and will give them a go tomorrow. I don't seem to be able to post attachments, but the 155gn projectiles, nearly every group I would get 3 shots in one hole - about 0.3", and 2 flyers which were further away and blew the group out to around 1". Not horrible accuracy, but not great. The 168gn Sierras seem much better.
I find it difficult to think that if it was a problem with my technique, brass or something coming loose etc, then why do the 168gn Sierras shoot so much better than 3 different 155gn projectiles?
I am just about due for a new batch of brass, I will see how that goes as well. I will also try to get hold of a chrony and put a few more shots over it to work out the velocity consistency.
As I said before, I am fairly happy with how the 168 Sierras shoot (though I will still try the 175s), I am not trying to work out what went wrong with the 155s, just seeing if there are any tricks/tips people have used on their F/TR to improve accuracy.
@ barrel-nut
I use the RCBS ChargeMaster Combo-Scale and Dispenser,
On my scale, I calibrate it with the two weights supplied. I remove the weights and the dispenser automatically zero's. It's calibrated. I then put the pan on it, then zero it. After every charge is thrown, I put the empty pan back on the scale and it automatically zero's before throwing the next charge. I guess your 750 doesn't automatically zero when you return the empty pan to the scale?before starting I put the pan on the scale and press "zero". This is a "tare" weight function- it basically just compensates for the weight of the pan. It should now read 0.0 with the empty pan sitting on it. Proceed to weigh charges. Periodically place the empty pan on the scale; it should still read zero. If it doesn't, press the Zero button to re-zero.
My question, do I need to till check the pan weight as you described above? I guess it's still a good idea to do so. It only takes a few grains of powder to change the weight. I thought about getting a scale that measure in .100's, but again with only taking a few grains to change .010's, I don't see the advantage.
Just curious
[B][SIZE=3]Dennis[/SIZE][/B]
To contine with the hijacking, concerning the powder charging...... :-\.....I use the RCBS ChargeMaster 1500. http://www.midwayusa.com/product/772...combo-110-volt The only time I have found a problem with this unit is if I happen to have a fan on during the summer, or if I have my heater with a blower on during the winter months when I am reloading in my garage. (A vented ceiling heater....don't worry guys....I'm not trying to ignite my house!!)
I have found that a small constant "breeze" will effect the scale. But, other than that, I always put the empty powder holder on the scale, then turn on the scale and it does it's start-up and goes to zero. I've never had a problem with it....and I usually go thru the zero process once a month, and I will on occasion toss on one of my weight checks just to double check the scale's accuracy.
My scale is now three years old and it's (knock on wood) still working fine.
FWIW
Dave
@ Dennis
I think our scales work exactly the same, except yours may not drift like mine.
I too calibrate using the supplied weights, then put the empty pan on the scale, and press ZERO. It now reads 0.0. When I lift the pan from the scale, it reads "-114.5", since my pan weighs 114.5 gn. When I put the empty pan back on it, it should automatically read 0.0. Any deviation from this, ie. "-114.6" when i lift the pan or "0.1" when I set it back on, is cause to reset the ZERO button. I hope that makes it clearer.
From reading customer reviews on Midway USA and Cabelas, it sounds like the 1500 you have is a better scale than my 750, so yours may not have these issues. And yes, Dave, definitely turn off the ceiling fan before using. Also, Dave your "avatar" photo cracks me up!
Quinny, how did those 175's do today?
Barrel-Nut..... ;D...Thanks. My brother gave me the idea to post my pic...
I thought of posting one of me working..............but the general consensus was....maybe not so much. ;D
That's hilarious! Scary thing is, I KNOW people like that! Good folks....
Quinny, any luck with the 175's?
This makes a lot more sense!when i lift the pan or "0.1" when I set it back on, is cause to reset the ZERO button
I will definetly watch this in the future!
LMAO ;DScary thing is, I KNOW people like that!
[B][SIZE=3]Dennis[/SIZE][/B]
I made up some of the 175's today using a couple of different powder charges from 42.5gn to 45gn of ADI 2208 (Varget). It was very windy out there - like 30-40mph which made things very difficult. The 175s seemed to shoot pretty well despite the conditions. I think that another round of testing may be needed to draw any conclusions with them, but it does look promising.Originally Posted by barrel-nut
Good- always good to have another reason to head back to the range!
Quinny,
I shoot a Varmint Model 12 FVSS in 308 26" barrel with a Bell & Carlson Varmint/Tactical stock, not bedded. I did well with 168s like you. Then I read where 168s lose stability beyond 600 yds. Did more research and found this to be an accepted belief/opinion among many. I shoot groundhog out to 1k. (well shoot at anyway) With 168s over 500yds only had 2 kills, and at 6 to 800 I was all around them with no hits. After reading that beyond 600 most recommended 155s or 175s I went to work on a new load. In short I did best with Varget,fed 210m primers,lapua brass,and 155 SMK. 175SMK did well but 155s were a little better. Results, I can shoot 3 shot groups in the .2s. Consistently shoots 5 shot groups in .5s. Killed 3 hogs over 700 yds. with limited hunting time, and many very near misses well over 600. Hope the 175s do you good.
As for scales. With mine I can have NO air movement. Ceiling fan must be off and if its breezy out I have to shut the window. I have to be careful with the scale in front of me that I don't BREATH on it. I use 2 pans, 1 always on scale for weighing and with the other one I get a charge from the powder drop, then zero the scale, pour powder into pan on the scale,weigh, trickle some as necessary, pour back into 1st pan, put empty pan back on scale, zero, then weigh again, if satisfied fill case. I do this with EVERY load cause my scale will drift. All loads are weighed twice. I'm sure I will wear out my zero button but oh well. Hope some find this helpful.
kd.
That is interesting what you say about the 168s losing stability over 600yds, I have never heard that report before. I have read quite a few people shooting the Savage F/TR recommending the 168gn SMK, which is the reason that I gave them a try. I have shot my rifle at 880yd with all 12 shots on target, having never shot at that distance before, and never shot lying down before.
All of the 155gn pills I have tried have not been very good in my rifle. I have not tried the 155gn Lapua's though, they may be worth a go. I will try another round with the 175s and see how they go.
I cannot confirm the 168 story. Just what I read and thought I'd pass it along and my experience. You cannot argue with impacts on the mark. If they work for you, shoot em baby shoot em. Hope you nail down a tack driver load.
kd.
When you are doing your prep work before reloading are you checking the head space of the shoulders on your brass, are you weighing your brass and bullets for consistency? All this might sound a little anal but it all does factor in, it could be the difference between a .5 MOA and a .25 MOA shooter. I have also found that high caliber rifles especialy msgnum rifles shoot better groups out at 200 yards than at 100.
Just a thought
I site in at 100, then go to 300 on Mag calipers! I can get better groups at 300 vs 100!!!!!I have also found that high caliber rifles especialy msgnum rifles shoot better groups out at 200 yards than at 100
[B][SIZE=3]Dennis[/SIZE][/B]
I do weigh my brass and bullets for consistency, but I don't neck turn the cases, check for concentricity etc - I don't have the tools to check headspace etc.
I plan on doing a side by side test of the 175s and 168s this weekend - same day, same shooter, and see what happens.
As already stated by Dennis, give 300 a try and let us know. Boattails in an upper caliber love to stabilize better at longer distances.
check the article on 6mmbr.com from the competitive shooter under .308. He said to back off loads from full-power. His loads with 175's are nowhere near max and he's using Varget it says how many grains....
I have the F/TR also but it's not 'set up' yet in the optics dept so I don't know how it shoots. The rifle is absolutely HUGE too...
I am considering putting a match barrel on the F/TR as well as bedding the action. I am wondering if anyone has done this with an F/TR and share their results - i.e. was there a noticable improvement in accuracy?
I use 175 smk's in same rifle. I quit weighing them but do measure the length to ogive on every bullet and sort them accordingly. You will find different lengths, sometimes .020 difference. They must be sorted and seated and oal to ogive checked again. Also get a runout indicator as a previous post said it will make a better handloader out of you, I know it did for me. I use 42.8 gr H4895 behind the 175 smk's for 3014 mv. I know it sounds hot, but I haven't had any problems. You must work up loads slowly to see if your rifle will handle them.
To the OP: How far off the lands are you seating the bullets ? What primers are you using ?
I must correct myself. The 42.8 gr load with the 175 smk is at 2832 mv not 3014. I confused it with a different rifle and load. They are 3.152 coal with a Sinclair nut, and I use Winchester WLR primers. I would have to check my chamber again as there is approx 2500 rounds thru this barrel and there is some throat erosion, but around .005-010 jump. Sorry for the screw up. Luckus
I'm so glad you cleared that up. I was trying to figure out how the he"" you got that kind of speed out of a 308! LOL
Vietnam Vet, Jun 66 - Dec 67
The bullets are approx 0.020" off the lands, I did some testing with various seating depths and that is what worked best. I am using CCI-BR primers and Lapua brass.
It is currently at the gunsmith to bed the action properly, will see how things go after that. Hopefully early in the new year I will get a match barrel put on.
3.152 OAL is huge for a .308, the bullets must be barely being gripped by the case. I know that with a 155gn projectile, my max OAL is 2.880, anything longer would not chamber as the projectile hits the lands. The 175SMK is much shorter than the 155s, so I have no idea how you managed to get it out to 3.152...
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