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hey guys,
i and my partner are currently haveing a grouping problem and can not figure it out rite now on how to correct it. we shoot 5 shot groups to give good group data and we are getting 3 that are on hole or tight clover then two that are any where from 1/4" to 1" away that are stacked also. what could this be, what can we do to take care of this? this is very frustrating.
posting in both reloading forums to get more responces from people who may not see the other post
hey guys,
i and my partner are currently haveing a grouping problem and can not figure it out rite now on how to correct it. we shoot 5 shot groups to give good group data and we are getting 3 that are on hole or tight clover then two that are any where from 1/4" to 1" away that are stacked also. what could this be, what can we do to take care of this? this is very frustrating.
barrel heating up?
What gun, caliber, powder, bullet, charge weight? Are the scope/base/rings torqued properly ? (I've had a lose ring cause flyers like that before)
Whats your velocity? Are all 5 shots about the same velocity?
My new 116 FCSS .30-06 does that, too. My best guess is that it's my cheek weld or my trigger pull. I'll have to let someone else try to confirm.
If I find it's not just me, the first thing I will do is try removing, then reinstalling the Accustock, with carefully measured torque.
the barrel warms up a little but we let them sit for a while before we shoot again
his is a mauser actioned 257ai 26" barrel 85 grn sierra varminter like 49 grns of i dont know what powder
mine a savage 243 ai 26" barrel magnum contour 70 grain ballistic tips with 48.3 grains of w 760 powder
havent chronographed either yet. will be getting speed next time out. i just made ten rounds of my best loads yet for this gun and am going to shoot them at a little range and see how they do all while every round is chrono'd
Sounds like barrel heat to me. Try letting the barrel cool down completely between each shot; use a fan to help speed this up. May take a little while, but that's the only way to find out for sure.
If the first 3 are grouping well, then #4 & 5 stack vertically, this is almost surely the problem.
+1, the magnum weight barrel heats up almost as fast as a sporter barrel.Quote:
Originally Posted by barrel-nut
As stated in the other post, barrel heat is causing the problem. Five shot groups are doable in a magnum or sporter weight barrel but the barrel must cool completely between shots or groups will open up. The norm for barrels thinner than varmint weight or bull barrels is three shot groups due to the fairly rapid heating.
Are you cleaning your rifle between groups?
I have found with all of my rifles that the first 2 shots from a clean bore will have a different point of impact from the next 15 or so...
If I fire a 5 round group from a clean bore the first 2 shots will be high and left, the remaining 3 shots will be .5 MOA. The following group (from a "dirty" bore) will be all 5 shots into .5 MOA. It will hold this accuracy for 3 to 4 groups before it starts to open up a bit.
I am shooting with heavy barrels and I allow anywhere from 30 seconds to 2 minutes cool-down between shots (depends on how impatient I get).
Please do not double post. Your topics was merged, and pulled out of the standard caliber due to them both being considered wildcat calibers.
It sounds to me like you have a lot going on, and there could be several factors causing your poor grouping problem. To start, do you have wind flags? Shooting without them is a waste of time. Yes, wind will GREATLY affect groups. They dont have to be fancy, just a few pieces of survayors ribben on sticks placed every 25 yards will do.
Second, What kind of rest are you using? A good solid set up, (Front rest or bi-pod and a good rear bag.) makes shooting groups much eaiser.
Third, What happens if you just shoot 3 shot groups? Are they all in one ragged hole. When developing a load I ony shoot 3 shooot groups. 3 shoots proves the load, 5 shoots prove the shooter.
Fourth, what all have your tried? IE powder, bullets, weights, (Both powder, and bullets.) seating depth, brass, brass prep, ETC. (It may be that your guns don't like wat your feeding them, let the gun tell you what it likes don't force feed it something that you read in a magazine or the internet that someone else is doing.)
Some things to consider, make sure the scope bases and everything else is tight. I find that with Factory Savage barrels they shoot thier best when dirty, usaly after 20 rounds. Experiment with diferent bullets both weight, and maker. Try diferent powders. I dont wait between shoots, I find that the barrel has extreamly hot to affect accuracy. Most bechrest shooters (Both short range and lonag range) try to get there shoots off as fast as they can (Depending on the conditions.) they dont worry about the heat generated by more than 5 shoots, and they shoot increadable groups.
Good information. I wasn't aware that barrel heat is not a "grimlin" to fixate about..............like I've been doing.Quote:
Originally Posted by 82boy
This is good information, except-
Barrel heat is indeed a factor for any barrel that has not been stress relieved. The button rifling process introduces stress into the steel that can and does cause shifts in the point of impact as the barrel heats up. If this were not the case, high end barrel manufacturers would not spend the extra money to have them heat treated (stress relieved).
Also, the thinner the taper, the more quickly the barrel heats up and the more it's groups can open up.
Benchrest shooters do indeed fire strings very rapidly when a favorable condition exists. They fire them through high quality, bull contour, stress relieved barrels, using rounds that burn a relatively small amount of powder, such as the PPC's or BR's; thus barrel heat is not an issue for them. It may, or may not, be for the OP. I was simply suggesting that he might want to test this out, because i have dealt with similar problems with factory barrels myself. I have two that will not group well for five shots fired consecutively, but do much better if given time to cool thoroughly between shots. These are hunting rifles, not benchrest rifles.
A high quality properly stress relieved barrel can be shot until it is very hot without much loss of accuracy. Most factory non-stress relieved barrels will not behave as well when hot.
Now, I not trying to start any fights, or flame anyone, but I believe that many people on the forums, put a bit too much concern on barrel heat. Now I am not saying that heat doesn't affect a barrel, or accuracy, because it does, but what I am saying is the point where a barrel reacts to the heat is much greater than many people believe. Yes, a 100 degree day with the sun at an angle where it is like a blowtorch on the barrel will greatly affect shots. What I am saying is the average factory barrel either sporter, or varmiter, will hold together good groups, on an average 75 degree day, in the manner that most ranges are set up with cover over the gun, with the shooter shooting 10 shot strings, without a break. (That is with letting the barrel cool down after 10 shot strings.) I see a lot of post where people say that wait a few minutes between shots, and all I am saying is that it is not necessary.
When I mentioned benchrest I used it as a example that you don’t need to wait minutes between shots. Yes in short range BR most shooters use a PPC, but in the long range BR you will see anything from a 6mm br to wildcatted versions of 338 lapua's, and other large powder volume cartridges. You will see mostly versions of the 6mm br but different versions of the 284 are not uncommon, as well as 7WSM's and 300 win mags. I would say that the shooters in the long range game shoot faster than the short range game, and it is not uncommon for them to shoot matches back to back with no waiting period in-between. Most matches have a 7 minute shooting period, (5 shot or 10 shots for record, and unlimited sighters in a period just seconds before the match.) and most all competitors are finished within 2 or 3 minutes.
I can contest I have shot a lot of factory Savages, in both sporter, and varminter barrel profiles. I have been blessed to shoot in Benchrest matches where they offer a factory class. I have as well as many others have shot box stock Savages in these matches. (Many times the exact same time as other shooters was shooting high end customs.) I can say that most of the Factory savages I have shot have been vaminter profile barrels, most of them are 22/250, many was 223, a few where 204 ruger, 243 win, 6mmbr, and one was a 308. Though the guns do not compare to a high dollar custom benchrest gun, I can say that the barrels behaved in the exact same manner as the higher dollar stressed relieved, barrels in both button rifled, and cut rifled. What affected the factory barrels affected the other in the exact same manner. I will say I have shot Savage factory sporter barrels and yes they are more affected by the heat, but I can still get them to shoot a 5 shot groups with little time in-between shots, and with a few sighters.
No fights or flaming intended, and none taken. I respect your opinion, and your experience is certainly greater than mine, but we may just have to respectfully agree to disagree on this one, as my experience has been different from yours. That being said, most of my shooting does take place in very hot weather, 95-100 is the norm in summer where i live. Weather, as you stated, does have a lot to do with this.
The ultimate goal here is to help out the OP by sharing our experience, and that was the point of my posts, not to start any fights.
I let my hunting rifles cool because I want my load to group on a cold bore. 99% of the shots you take in a hunting situation are on a cold bore.
I shoot on a somewhat primitive range with no cover from the sun (no benches or target frames either, (had to build my own portable setups). During hot summer days here in central Georgia, my barrel (especially blued ones) can get too hot to touch just sitting in the sun let alone being fired. I've see groups open up shooting a magnum with a factory blued sporter barrel after just the first three shots and continue to get bigger after subsequent rounds fired.
What 82boy says is most likey true to a great degree. I can't argue with him as I've never shot a sanctioned benchrest match on a nice range. What I do know is MY accuracy is affected by a hot barrel whether it's a fault of the hot sun or X number rounds through the barrel or possibly a result of the combination of conditions. Obviously, barrel life for match shooters can be short because of barrel heat in a match and not rate of fire. It's no wonder some barrels are no longer competitive in as little as 800 rounds.
I can't afford to replace barrels often so will stick with letting my barrels cool as best they can considering my conditions.
how do you know if you have a neck tension problem?
You can feel it when you seat a bullet, seating effort will be real light because of neck spring back. This is a sure sign the brass needs to be annealed.Quote:
Originally Posted by calib
ga cop-
what about getting a light ring in my bullets when seating them? could that be a sign. other than annealing what can i do? this brass is only on its third loading
The light ring on the bullet is from the seating stem and has no brearing on accuracy so can be ignored. What brass are you using? Try polishing the expander button on your sizing die to see if that helps. I use a Lee collet die and found neck tension is much more uniform and my neck runout is usually afround .002".Quote:
Originally Posted by calib
in simple terms can you explain runoutQuote:
Originally Posted by GaCop
how much the entire loaded round is out of a true straight line from center point on the case head to the point of the bullet.
this is why I never use my sizing dies to decap. Decapping pins get bent while decapping and when it does it will cause runout.
+1. There's bullet runout where the bullet is cocked in the case neck and when bad enough, you can see the bullet wobble when rolling the round on a sheet of glass. Neck runout causes the case neck to be cocked off center by a bad sizing die or bent expander stem.Quote:
Originally Posted by keeki
I always use a universal decap die, its a must have if you use Lee collet dies.
thanks for the info ill have to take a look and see if i can notice any wobble
to check this your gonna need a concentricity gauge. We're talking .003" is too much.
I had this same problem with my .308. I would have two or three touching then it would jump a inch or so up and group two more. I tried all sorts of things to tighten my groups to no avail. Come to find out my scope rings were loosening up and ever so slightly moving on me. Now i lock tight them and shot my best group of 4 shot .397" at 100 yds.