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View Full Version : Help me analyze my groups?


glug
05-19-2012, 5:47 PM
Hi,

I'm still pretty new to precision rifle shooting but am working hard to get better. I am only shooting from 100 yards at this point but would like to progress out further as my shooting improves.

I have a Remington 700 in 308 Winchester and have done some basic things to accurize it (free-floating barrel, 3 lb Timney trigger, bubble level for good measure). I shoot from a basic front rest and rear bag (no lead sled or anything like that).

Without further ado, my results. All from the same shooting session at 100 yards:

1st "group" if you can call it that was from a cold, clean bore and cheap 150 grain American Eagle. I am not sure what was going on here. I know this isn't the best ammo but I would still expect at least 1.5 MOA, not 4 inch groups. I'm assuming shooter error and maybe I was still getting my technique down...

https://lh5.googleusercontent.com/-hxUV1HYndkY/T7bRTBPyp3I/AAAAAAAAjd0/JaCc8PGgRF4/s1024/IMG_20120518_110640.jpg

2nd and 3rd groups I switched to Federal Gold Medal Match and they were much more respectable. I measured them as 1" and 1/2" respectively. I adjusted the zero on my scope to get on target between the two.

https://lh3.googleusercontent.com/-nzAs_9k0ZFY/T7bRfOSIh3I/AAAAAAAAjeM/ITmx_MgOEXY/s1024/IMG_20120518_113007.jpg

https://lh3.googleusercontent.com/-sobc3zjOAA8/T7bRhSi7nrI/AAAAAAAAjeU/o-aH_pVUg2w/s1024/IMG_20120518_115240.jpg

Finally I did a 5 shot string of my own hand loads (first time ever, so I was happy just to come through it unscathed). I think it came out pretty well, but I have no idea what to make of this. Is it a single 1" 5-shot group, or is it two 1/4" groups? I'd be amazed if it were the latter...

https://lh5.googleusercontent.com/-yjJDtoUzigQ/T7bSBCQyAyI/AAAAAAAAjew/wFZizFDUA-A/s1024/IMG_20120518_121555.jpg

The two shots on the right came first, then the 3 on the left. Unfortunately I wasn't paying attention to the wind... maybe it shifted and that was the cause? I was shooting very slowly, probably a few minutes between shots.

Any insight would be welcome. Thanks!

USMCforLIFE
05-19-2012, 5:57 PM
at 100 yards it wont effect that round thats not bad just control your breathing as you exhaling slowly squeeze make sure you don't hold your breath once you hold your breath you start to shake

USMCforLIFE
05-19-2012, 5:59 PM
what ever the first rounds are WTF at 100 yards it should be no where near that big of a group especially if you are using a rest. ditch that ammo spend the extra money its worth it

DirtRacer151
05-20-2012, 10:21 AM
As far as the last group posted goes... Did you have all of the parallax properly adjusted out of your scope?

Merc1138
05-20-2012, 10:55 AM
Hi,

I'm still pretty new to precision rifle shooting but am working hard to get better. I am only shooting from 100 yards at this point but would like to progress out further as my shooting improves.

I have a Remington 700 in 308 Winchester and have done some basic things to accurize it (free-floating barrel, 3 lb Timney trigger, bubble level for good measure). I shoot from a basic front rest and rear bag (no lead sled or anything like that).

Without further ado, my results. All from the same shooting session at 100 yards:

1st "group" if you can call it that was from a cold, clean bore and cheap 150 grain American Eagle. I am not sure what was going on here. I know this isn't the best ammo but I would still expect at least 1.5 MOA, not 4 inch groups. I'm assuming shooter error and maybe I was still getting my technique down...



Based on your other groups, your rifle hates this ammo. Don't buy it again.

2nd and 3rd groups I switched to Federal Gold Medal Match and they were much more respectable. I measured them as 1" and 1/2" respectively. I adjusted the zero on my scope to get on target between the two.



If you want to keep buying commercial loads, get this or better. I'm sure you noticed the price difference between the gold medal match and the crap 150gr ammo. There's a reason for that.


Finally I did a 5 shot string of my own hand loads (first time ever, so I was happy just to come through it unscathed). I think it came out pretty well, but I have no idea what to make of this. Is it a single 1" 5-shot group, or is it two 1/4" groups? I'd be amazed if it were the latter...

The two shots on the right came first, then the 3 on the left. Unfortunately I wasn't paying attention to the wind... maybe it shifted and that was the cause? I was shooting very slowly, probably a few minutes between shots.

Any insight would be welcome. Thanks!

I don't get why you'd think it was 2 small groups if you were shooting 5 shots at the same point of aim, it's a 5 shot group. Like DirtRacer151 pointed out, might be a parallax issue, maybe you changed your cheek weld?

bombadillo
05-20-2012, 11:13 AM
Oh ya did that last one all wrong! you're supposed to put a quarter over the group on the right and have a 1/4MOA group on the left :D

Just kidding, just kidding. Anyway, it obviously got progressively better so it appears as though all your gear is working properly and there is no problem there. The top group is kind of crap and maybe you were just flinching a bit but the hand loads did really well as did the FGMM. As you go on, it will probably get better with breathing, shooting between heartbeats, (don't let anyone say its hard or call you a liar because its simple once you take the time to really slow down and feel it. Helps if you double up on hearing protection too) and just trigger time in general. I'd bet you could get sub-moa all day long with a quality hand load, and maybe a bipod on the front with a rear bag. No need for lead sled or anything like that unless you're really testing out hand loads and want to make sure the shooter error is out of the equation completely. The thing is, even if you can put 5 shots in a single hole at 100 or more on a lead sled, it doesn't help you in the real world if you can't shoot 3" off-hand groups on 6x repeatedly. If you're hunting, test out leaning against a post, kneeling position, prone, and outright offhand shooting if you can't get to one of the other positions. Also try practicing with slings and other methods. Hope this helps, and good shooting!

glug
05-20-2012, 11:33 AM
Thanks guys. You're right on the last group it could definitely have been a parallax issue, as I was having some trouble with that. I was just surprised at the consistency of the last 3 shots on the left after the first 2 on the right so that's why I wasn't sure what to make of it.

Even with my side focus adjusted to eliminate as much movement as possible I still could see a little sidewise play. What I tried to do a few times to get around it was back way off the scope to the point where the parallax went away and steadied the rifle on the rest, then crept back up into shooting position trying not to disturb anything. My scope is a Millett TRS-1 so it's probably the weakest link in my setup at this point but I don't want to put big money into a better scope just yet.

I guess I just wanted to verify that the rifle and ammo were at least sub-moa or better and then work on my shooting technique from there, moving on to shooting from a bipod and other positions.

One thing that still really gives me trouble is getting back on target after every shot. When I fire I do my best to keep my eyes on the target and not flinch but the rifle still ends up jumping around and I can't see a thing. When it settles down I am usually pointed half-way over to the next lane and have to start from scratch again... I feel like if I had better form and maybe used the sling it should come back down pretty closely on target.

bombadillo
05-20-2012, 12:14 PM
One other thing you can do is adjust your scope to shot 1-2" underneath your target for grouping. That way when you hit the mark, you are still aiming at the exact same thing, but your group is a tad high or low. Then you put up a 1/4" shoot-n-see dot so you're aiming at a small target and watch your groups shrink. If you hit the dot, all of a sudden your target changes and that causes people to drift right or left. Aim small, miss small.

Gunsrruss
05-20-2012, 2:28 PM
your reloads seemed to work fine. I think you should stay with your own loads and build some confidence in them. Maybe tweak them some as you see fit.
Happy shooting Sir. You seem to be on the right track.

Switchbarrel
05-21-2012, 1:31 PM
Hi,

I'm still pretty new to precision rifle shooting but am working hard to get better.

I shoot from a basic front rest and rear bag (no lead sled or anything like that).


I'm assuming shooter error and maybe I was still getting my technique down...


The two shots on the right came first, then the 3 on the left. Unfortunately I wasn't paying attention to the wind... maybe it shifted and that was the cause? I was shooting very slowly, probably a few minutes between shots.

Any insight would be welcome. Thanks!

There's probably a dozen things going on here. The first group, the rifle obviously doesn't like the load. Save that stuff for fouling shots after cleaning.

Not being there, these and things mentioned above are only guesstimates at best. Technique plays a huge role as well. Are you holding the rifle the same from shot to shot? Are the benches at your range stable? Are you sure. If I change how I lean on the bench at a couple of ranges I frequent, I can watch my crosshair move across the target (I use 42x Nightforce and
50x Sightron scopes).

Is your rifle stable in your rests or does it torque around when you fire (another consistency issue)?

At longer distances things become more pronounced, we look at vertical as being a function of your ammo's consistency and windage as....you guessed it - wind conditions.

Your handloads look like a good start. Try again, this time paying attention to the wind conditions. Shoot faster trying to get them all off in the same condition.