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dacaur
10-01-2011, 04:05 AM
Second time this has happened to me..... I was at the range today to test of seating a little deeper would increase accuracy, you know, read an article in a mag.... nope, groups opened up to 2+ inches with shots all over the place when I used an COAL of 2.7975 and 2.7960 rather than the 2.8 I have been using (.308 win, hornady SST 165gr, 43.8gr of varget) Not that I am unhappy with the accuracy I am getting really (savage Edge resting on my shooting bag)....

Anyway, I decided to shoot one last group with my standard 2.8" COAL just to make sure it asnt the gun acting up that opened up my groups, the first three rounds formed a perfect 3 leaf clover touching at .383" center to center, the 4th opened it up to 1.05", and the 5th to 1.995".... Shoulda quit while I was ahead... lol....

(edit - I just realised I put 2.975 and 2.960 rather than what it should have been 2.7975 and 2.796)

GaCop
10-01-2011, 06:15 AM
Can happen due to the lighter sporter barrel heating up fast. Three shot groups will pretty much tell you if the load is going to work for hunting.

wbm
10-01-2011, 05:35 PM
Can happen due to the lighter sporter barrel heating up fast. Three shot groups will pretty much tell you if the load is going to work for hunting.


It sure will. How many times have you read "three shot groups don't tell you anything." Sure they do. It tells you out of a cold barrel how well you're rifle shoots three shot groups! If you ain't killed it with three shots, either quit or run...which ever seems appropriate at the time.

82boy
10-01-2011, 07:18 PM
3 shot groups prove the load, 5 shot groups prove the shooter.
A few things to add: magazines don't always give the best advice, and each barrel has its own personality. To sum it up, what works for one barrel more than likely will not work in another. Find what works best in your barrel. Second if your shooting without some sort of wind flags you are wasting your time. If you think the wind doesn't affect the bullet, or that you can see changes without flags, you are fooling yourself. Now with that said, I would shoot three shot groups and play with what is working, try going in and out on seating depth in small increments. You may find that your barrel likes more jump. I have seen some guns that shoot their best .050 (and more) off the lands or jumped. Once you have the three shot groups to where it is shooting a ragged hole, then try 5 shot groups.

dcloco
10-01-2011, 11:04 PM
Quit using SST's.....try a target bullet...it helps.

AMax's work well for shooting groups.

My 308 likes of diet of 168 AMax, 168 HPBT's, 176 & 178 HPBT match bullets.

CJ in WY
10-02-2011, 12:28 AM
If you ain't killed it with three shots, either quit or run...which ever seems appropriate at the time

Three shot groups seam to work best for hunting rifles but the prairie dog guns gotta get 5 where they belong.

hub
10-02-2011, 01:51 AM
Three shots test the rifle. Five shots test the shooter. ::) ::) ::) ::) ::)

GaCop
10-02-2011, 06:00 AM
I'm working up loads for a 30-06 sporter. I tested loads yesterday with IMR 4350 and charges from 56.1 to 56.8 grains pushing the 155 grain A-Max. My best load was at 56.5 grains yielding a three shot group of .372", C to C, at 100 yards in a variable 10 to 15 mph wind. The A-Max was seated .042" OTL. I did prep my brass by uniforming the primer pocket, deburring the flash hole and trimming all brass to the same length.

Another test shooting four groups of three will determine if the initial results were a fluke. I let my barrel cool about two minutes between 3 shot strings. If you get consistent sub MOA 3 shot groups, I'd stick with that load for hunting.

dacaur
10-02-2011, 02:54 PM
Quit using SST's.....try a target bullet...it helps.

AMax's work well for shooting groups.

My 308 likes of diet of 168 AMax, 168 HPBT's, 176 & 178 HPBT match bullets.


I'm using SST's because they are what I am going to hunt with, and hunting is the reason I am developing this load.

I dont know how far off the lands I am at 2.8"COAL, but it seems to work.

My gun is pretty consistent in that when shooting 5 shot groups it will normally do a good sub MOA 3-4 shot group then throw the last 1-2 shots an inch away.... its a savage edge, so I have no illusions this is any type of bench gun... ;D

willyp
10-10-2011, 06:27 AM
Dacaur,I have had a 308 for 15 years. I've tried a lot of different bullets and different COL's,but,i keep coming back to the 2.80! It seems to work best.

racinready300ex
10-10-2011, 12:34 PM
I test with 3 shot groups most of the time. If I can't get 3 shots in the right place, 2 more wont help. I'll save the bullets till I get things figured out. Then I'll shoot a couple 5 shot groups to confirm. But the real test comes on how I do at the next match.

darkker
10-10-2011, 01:36 PM
Well, the three to five argument is one of semantics.
I shot 5 shot groups, but don't pound them down the barrel. I give a good 10 second gap between rounds.
The reason I do 5 is exactly because of barrel heating. I WANT to know how my gun reacts, and where things move to.

I also shoot (in testing) through a chrony, so 5 shots gives me a much better statistic for averaging... The old story about 1-time's got no case.
FWIW

dsculley
10-13-2011, 02:54 PM
On the 3 shot/5 shot and barrel heating controversy: I have a friend (former LEO) who loads his rounds to compensate for the barrel heating. Rounds 2 - 5 have the powder adjusted to compensate for the heat buildup. The adjustments to powder are a result of a lot of trigger time and load development. His custom/home built .308 has a sporter barrel and his 5 shot groups can usually be covered with a dime.
This takes time, but since he is retired that is no problem for him.

handirifle
10-13-2011, 11:30 PM
Second time this has happened to me..... I was at the range today to test of seating a little deeper would increase accuracy, you know, read an article in a mag.... nope, groups opened up to 2+ inches with shots all over the place when I used an COAL of 2.975 and 2.960 rather than the 2.8 I have been using (.308 win, hornady SST 165gr, 43.8gr of varget) Not that I am unhappy with the accuracy I am getting really (savage Edge resting on my shooting bag)....

Anyway, I decided to shoot one last group with my standard 2.8" COAL just to make sure it asnt the gun acting up that opened up my groups, the first three rounds formed a perfect 3 leaf clover touching at .383" center to center, the 4th opened it up to 1.05", and the 5th to 1.995".... Shoulda quit while I was ahead... lol....


I hunted with my 308 this fall, got a nice fat forkhorn and he sure tastes good ;D. I used the Nosler Etip and reading the Nosler data, they say to start .050" off the lands. When I checked this length on my Savage, it came out to 2.845" so that was where I put them. I had about 25 loaded with different powder weights of IMR4895, with 45gr being my top load. 47.3gr is listed as a max, compressed, load, but I can tell you for a fact that my load of 45gr is compressed as well, since the bullet goes in beyond the bottom of the case neck, and the powder sits above the bottom of the case neck, before I seat the bullet. Nosler says to use the same data as their other 150gr ballistic tip bullets.

Anyway, they also list 2.800" as the COL. I was running out of bullets before, and season was due to open just a couple days away, so I settled for the load. I was getting 1.1" groups, so I was happy. The shot was at 180yds and hit where it was supposed to, so no complaints there. So now I am wondering if it is worth the $$$ to test loads seated deeper, or just stick with what I have. I picked up another box of them today, but with these bullets (CA lead free rules here :-\) costing me $44 out the door for 50, I cannot afford to just fling away, but your info sure makes me wonder if I might just close the group up even more.

GaCop
10-14-2011, 07:24 AM
Sounds like your load is performing well for you. Unless you just need to experiment ( and more trigger time), I'd stick with what has been shown to work.

dacaur
10-14-2011, 03:49 PM
Yea $44 for 50 seems pretty steep, I sometimes have trouble coming up with the an extra $35 for 100 SST's....

Not sure what to tell you there. Based on my own experience seating deeper didn't help me. And 1.1" groups are nothing to sneer at to start with....

Here is something you might try... In the article I read, The author also used e-tips for hunting, but does load development with another cheaper round with the same shape. He was getting like, .74" groups with the lead core bullet, but with the same OAL and powder charge using the e-tips his groups were around 2", so he started incrementally seating deeper until his groups shrunk back down.....

So it might be worthwhile to get a box of cheaper bullets and develop a load and see if you can get groups significantly less than your current 1.1". If not, then you didn't waste a bunch of e-tips, if it does, then try seating deeper, either way you get to do a bunch of shooting so its win-win, right?

On the other hand, it might be worthwhile to just load up 5 rounds of your current load seated to 2.8" and see what happens....

hank mcmauser
10-16-2011, 01:34 PM
shoot a 3 shot group, then next time at the range take same target,and center another identical target over the first one, keep doing this for several range trips always putting the 1st target below the new one. After several trips you will then get an idea of what the rifle,and shooter is capable of. you could do the same with one or even 2 shot groups,you are wanting to know what the rifle does on it's first cold shots especially for a sporter.
Both mine and my daughters 110's like the 130 gr. over a reduced loads of either 4350 or varget, I load them to appx 2650-2700 fps fps thereabouts,and both of them shoot better than we can see/ hold the rifle. The lee reloading book has a formula for reducing loads using powders that are deemed safe for doing so.

Luckus
10-16-2011, 09:41 PM
For load development I went to four shot groups a few years ago.

DanSavage
10-21-2011, 05:56 PM
For hunting I shoot 3 round groups with cold bore and clean barrel, but for match ammo I test with 5 shot groups with a hot barrel. I shoot several sighters off a clean barrel until it starts grouping good, then move on to testing the different charge weights shooting the round robin method. In the picture below my 43.3 group had the best 3 shot group I ever had, it measured around .018 but then the 4th and 5th shots to that group opened it up to a little over 1 ''. The 43.7 load is the one I was looking for a match when your shooting 20 shots at a time in less than 30 min. The 43.7 group is a little over half moa which is good enough for short range F/TR. I fired these 19 shots in 12 minutes.

10fp .308 varmint barrel
Varget powder


http://i1011.photobucket.com/albums/af240/243Wilson/Mod.jpg


Hunting load work up with Nosler Ballistic tips.

http://i1011.photobucket.com/albums/af240/243Wilson/308sgroup001.jpg

romulus
10-21-2011, 06:14 PM
It's something a lot of people avoid talking about because it makes people mad and they start ranting, "You think I can't shoot? I can shoot!", but I've always wondered about target acquisition resolution on average.

How well can a shooter that practices 1-2 times a week (30-100 shots) hold his stadia on a certain size (let's say .3 moa) target? I used to shoot at 1" square stickers at all distances. Then I tried shooting the round pasters that are a little smaller. Now I shoot at staples at 100 and 200 yards and I do think it helps shrink groups by eliminating spare room and focusing on a small thing.

Shooting at staples does make your groups look huge in your scope (well at least to me) but mine measure a bit of improvement.

At 420 I still feel like the .75" or 1" pasters are too big for me to feel like I am aiming at the same exact point every time.

I use profiling on corners or unique parts of targets when I feel they are too big. I don't mean to hijack but does anyone else have strategies, experience, or shootin' theories about this?