Model 12 BVSS .223 Rem - Unpredictable Accuracy

[TnTom]

Ive run about 240 rounds total including the break in rounds (100) various loads numerous times, 10 rd groups. I can get some .3's/.4's then things get out their until I find whats loose. Loosening of the action screws but thats all been taken care of. I glass bedded and things looked much better and things went south again. Weird groups. I know when I can attribute the heat or the wind etc. cleaning requirements etc. Ive examined the bore and see no issues, crown is good. The front rest i use was a contributor once, things were loose, too hard of a front rest. Fixed it. It's a 1/9 twist barrel I use 69 gr and did no better no worse with 75's and 77's Varget powder, a couple of others. Always wiped the bore well after I changed powder.

All in all I'm stuck in a .5-.7 ball park and not liking it. Ive never had a rifle I couldn't dial in during the brake in or by 200 rounds for sure By dialed in i'm saying and consistent, predictable .5 and less. even a consistent .7 I can live with.

I noticed when I had the action and barrel off to glass bed it that the rear trigger guard screw was loose again I noticed when I was ready to put it back together again that there was no wood to hold the T/G rear screw no wood. When the trigger port was milled it was cut about half a screw width too deep rearward and there is nothing for the screw to grab hence it always loosen up.

Ive tried to build it up with filler and that didn't work. There isnt enough material to glue in an insert. One might say that since that screw doesn't hold the action and just keeps the rear of the guard up it shouldn't impact accuracy. My plan is to remove the trigger guard machine a bushing to support the rear action screw and shoot some groups with the trigger guard off.

This is about to wear out my last nerve. the scope isn't the issue either.

I have to make a few decisions. Can the rear T/G screw screw up harmonics if it isn't grabbing wood properly? I wish.

[hailstone]

Isn't 1 in 9" twist barrels more for the lighter weight bullets. Mine shoot the 50's and 55 grain pills into very small groups. Use lighter or heavier bullets than that and the groups open up. That's been my experience with a Stevens 200 and several AR's.

[tunered]

I dont think the TG is any problem, mine shoots 69SMK very well at25.5 Varget, 205m primer,2.325 Oal, full length Win brass, 75 Amax at 24.5 varget, 2.458 Oal same brass,primer, the 77SMK shoots almost as well with same load as the 75, I would look at your brass, use out of same lot. ed

[dcloco]

Mix up some 2 part epoxy (bedding compound), fill the hole for the rear trigger guard screw, let it dry, then drill a starter hole, and thread your rear trigger guard screw into the bedding compound/epoxy.

Are you FL or neck sizing for fired brass?

What is your bullet runout?

In all honesty, unless you are sorting bullets by weight/bearing length and checking runout on loaded rounds, 1/2" groups are good.

I would also suggest checking accuracy at 200 yards.

[82boy]

How do you know the scope is not an issue?
9 times out of 10 a unpredictable gun is a scope sissue.

[TnTom]

Brass is sorted, bullets are sorted, r/o is never greater than .001" or less mostly .0005" to 0.0, I have the same results with the Weaver T24, and my Redfield 10x, I have a Ruger Mk II in .220 Rocket and my Colt AR .223 White Oak Upper and the scopes reflect no problems when I put thse on that gun.

I fire form the brass and then neck size and head spacing is .0015" and after 5 firing F/L size. Brass is from the same lot, Lake City. No signs of pressure and when I chrono sd is always less than 10.

I have not shot anything less in weight than 69gr Seirra, berger, noslers and Lapua. most with B4s and Varget 25.5. I bought some 55gr HPBT and 53gr Hp and will see how they do.

Ive run from .001" jump to .020" and there seems to be no preference. All my loads are methodically loaded. Maybe the lighter bullet will make a bit of difference But a 69 gr bullet should hit .5 and under consistently. In my experience with my 1/7 White Oak upper 77gr were not hard to manage and a 1/9 should handle 69gr. The rocket is 1/8 and handles 69s thru 77s with no issues. I shot it in MR matches with no issues, My .220 Rocket no issues. My Savage is making me an unhappy camper.

I have built up the screw hole with epoxy, better for now. Ill possibly need to mill out more wood and make a larger epoxy block for the screw. I don't torque the screw more than 10 in/lbs and I torque the action screw to 25 in/lbs and I use blue lock tight that cures 24 hours before I shoot it.

I check my case neck wall thickness and don't turn them if they show greater than .0015 i toss them. I do anneal for my Rocket and for my AR I have not for the Savage but probably will at some point. If the sd starts to grow I have found I can bring it back down with the annealing.

Maybe the lighter bullet will help. Well see.

[oldguy]

My 12 in 223 prefers the 52 gr match the 69 smk varies too much so I don't load it instead use a 50-55 grain match
bullets which shoot a consistant .400 I believe to do better I need to shoot more. :-\

[glockeyed]

interesting... mine hates the lighter stuff. i just tried 52gr and it printed well over an 1in, and 68 printed .4. i have some 75gr to try next.

[Tozguy]

Just a thought but the rear rest might be an issue. You mentionned how the front rest needed fixin so how about the back? I didn't realize how important it was until working on my rear rest. If the rifle doesn't slide back close to previous aim point then its worth looking into.
Sierra's 69 SMK shoot superbly well ALL THE TIME in my 8.5 twist 28'' barrel with 24.0 of Varget so I would stick with them until you have your hardware sorted.

[oldguy]

Honestly I may be wrong here but once a rifle is down to .500 consistently to go lower lies in the shooters hands,
simply an opinion.

[1Shot]

...I've shot alot of holes with 40"s to 69"s in the 1-9...It comes down to the load & trigger time...
..69gr Sie. 25grs Varget, Lapua brs., 205M prs....3@100.. close enough for load work....

http://img.photobucket.com/albums/v692/sqek/SMK.jpg

[borg]

So the problem is that the group size varies between 0.5 and 0.7"? Isn't that pretty much a 0.6 MOA gun? I'm really confused as to what exactly it is that is upsetting you. You say even a consistent 0.7 you can live with, but it sounds to me like you are consistently shooting that and better. How can you not live with that? Are you getting larger groups, like 1.5 MOA?

It seems like you really know what you are talking about, but at the same time you are claiming to shoot between 0.5 and 0.7 MOA which is neither shabby nor especially inconsistent. That is a difference of +/- 0.1 MOA, so I have to agree that this sounds well within the range of shooter error.

[TnTom]

Thats a nice group. How many rounds can you shoot in one group before it opens to say .5? Please don't misunderstand my question, What barrel do you use. Is it a Savage?

I looked at all my groups 69 hpbt 25varget B4's LC this evening and considering the number of variables that I have mixed in, what ever is outside of the .7 +.2/-.3 (.4 to .9) tolerance zone can be explained so really maybe things are closer to consistent or capable becoming consistent than I'm considering. I need to be careful and not start making myself believe it should shoot .3 10 shot groups because it wont. Should it shoot .5 10 shot groups? Factory barrel box stock except bedded? I don't think so, I wouldn't bet on it.

Also a 10 shot group at .3 is harder to come by than a .7 but there may be 2-3 .3"-.4"'s in the .7" 10 shot group.

I've loaded up some 53hp and 55hpbt seirra and will see what happens this week. When I went back though my targets and data my 69gr seirra 25gr varget b4's LC brass were .4 to .7 and they were all 10 shot groups. I'll know a lot more at the end of this week.

I also think heat is playing into it more than I want to believe. Ive sort of ignored the heat waves. I shoot a group and then do some numbers and the next group starts with a cooled barrel.

I guess I was anticipating problems from the beginning when I noticed that the scope mount holes are not in align with the bore. but that does have any impact on group size just point of aim. The wood missing in the trigger guard screw hole, it was milled into the screw hole, doesnt affect group size, annoys me though because I had to deal with it and I had to deal with the misaligned screw holes and that's very annoying. I think a lot of shooting can be impacted by the frame of mind the shooter has or is in. It can really vary to. I try to leave my issue off the range. But you know how issues can slip in sometimes.

All in all I think the Savage is a good gun but I think they are really getting a couple of things ass backwards. Very cost conscience and they might have cut cost in processing where maybe in the long run it could catch up. If I were to buy another I check 3 things right out of the box and if they were wrong I'd box it up and send it back. So now that I'm done venting I'd probably buy another.

Ill report on the lighter bullets.

[1Shot]

...It's a stock VLP...Never shot it to see how many rounds it would take to open up...After load work it does'nt see much paper after that..Just varmints...Flying & walking.. ;)...To shoot under .5 everytime you go out to the range..You're going to have to load at the range to the conditions of the weather..Plus take plenty of chill pills with you..lol...I know when the conditions are right she'll shoot dead on...If it shoots .5 a week later I don't worry about it..Because I know it'll hit whatever the crossshairs are on..Be consistent on what you do..

[Snowwolfe]

Don't understand what the complaint is. If I owned any off the shelf rifle that would group 10 shots into .5 to .7 day in and day out I would be tickled pink. Instead of being disappointed you should be extremely happy.

[gotcha]

Tn Tom, Your 1st post you mentioned bedding the action and said; at 1st The groups tightened up then went "south" again. Struck me as curious. Did you change action screw torque? Did you remove stock and re-attach? Did you use a "stress free" bedding technique? Is it possible that your rear tang is contacting the stock and causing a different "set" each time you remove and replace it?Cause it seems you've been doing a lot of that. You seem to be a pretty thorough guy and this may not be the issue Just tryin' to help. Also, I've had problems w/ front rests and THOUGHT I'd fixed it. I switched to a Harris bi-pod and the groups shrunk significantly!! Used a "V" notched rear bag & slid to & fro to Lock in elevation. It worked real well for me. Again, not trying to be insulting but a good way to determine how steady your hold is can be determined by dry firing. Try it w/ your current rest. Shooting ten shot groups can be an exorcize in masochizm! How fast do you shoot ten shots? Barrel heat mirage could be coming into play. If you're like me, sometimes I don't see the forest for the trees ;D With all the talent available here (not me) somebodies goin' to come up w/ an answer. Keep on keepin' on ;) .5" to .7" isn't terrible 4 a factory bbl.

[TnTom]

I'm heading to the range tomorrow. I'm sure tang is floating with about .005" plus clearance. I have had it in and out of the stock working on the rear trigger guard screw hole but have been re-torquing to 25/27 in. lbs. I always check but dry firing a number of time to assure the cross hairs stay on the point of aim. I use a V-Notch rear bag and do the same for returning to zero. I apply baby powder to both and it makes them slick. Ive got the trigger at 1.7lb. I'm leaning toward heat and plan to measure barrel temp tomorrow and keep shots at 1 minute intervals. Ive looked pretty close at the crown and don't see any signs of damage and never pull a brush back against it but may have it recut to an 11 degree. I think its heat. we'll see. Thanks guys for all the feed back I'm taking my back-up scope with me tomorrow although I don;t think I'll have to put it on.

[borg]

Whoa. 10-shot groups? I originally questioned that in my post but took it out because I assumed you meant that the 10-shot groups were during the initial 100-round barrel break in, where something like that would be more common. Try shooting 5-shot groups instead to decrease barrel heating issues.

[Tozguy]

Wouldn't be in a hurry to cut crown to 11 deg. if you don't see any reason to. I think it was Speedy that made a case for a 90 deg crown being best when there is any variation at all in width or depth in the lands and grooves. Production barrels probably have more variation in this regard than custom barrels so consider carefuly.
The idea of five shot groups makes sense to me. Another consideration is to measure group vertical only unless you are very good at doping the wind. At the level of accuracy you are at there are a lot of details to check. It might be worth asking another good shooter to do a few groups with your gun... this can lead to some helpfull observations.

[hailstone]

Although ten shot groups are a little over what's needed nothing wrong with that sample size. In reality he is closer too meaniful data than those who shoot three shot groups. Much easier too blame technique, wind, called shots etc with small groups than with large samples. Believe Hatchers book contain a few paragraphs about this subject. Seems the Army was testing rifles shooting twelve or fifteen shot groups. War was going, supplies were short. Someone questioned whether they needed too shoot such large samples. A mathmatican was employed who used statistical methods too determine the optimum sample size needed. Analysis results showed that seven shots were required too obtain significant results. Less than those number of shots left uncertainty as too true accuracy. More than that number only wasted precious ammunition needed for the war effort.

Try it sometime. Lots of those wonderfull small three shot groups will open up when there shot correctly using proper statistical sampling. Believe thats part of the reasoning for large number of shots whether it be competition or qualification.