What does this grouping mean?
- Thread starter Tac-O
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dfanonymous
Well-Known Member
- Joined
- Jul 16, 2016
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Did you or do you commonly adjust your face on the gun? Looks like the trigger discipline is there, that pretty much leaves you imparting a pressure in two different way would be a pretty good guess, or some weird coincidence of SD.
aushunter1
Well-Known Member
You need to give a whole lot more info when asking these kinds of questions like-
Ammo type?
Rifle type?
Rest type?
trigger pull weight?
Consistent shooting position?
Have you checked-
Base & scope mounts?
Action torque?
If I had to have a guess without knowing all the above details I would say adjust ammo seating depth(if your handloading).
Check & or adjust action torque to accordance with stock type, some rifles like less on the front & more on the rear, some the reverse, some even pressure.
Without more info cant really offer much else.
Ammo type?
Rifle type?
Rest type?
trigger pull weight?
Consistent shooting position?
Have you checked-
Base & scope mounts?
Action torque?
If I had to have a guess without knowing all the above details I would say adjust ammo seating depth(if your handloading).
Check & or adjust action torque to accordance with stock type, some rifles like less on the front & more on the rear, some the reverse, some even pressure.
Without more info cant really offer much else.
Hawkeye Pierce
Well-Known Member
is your is your Barrel truly free floating? I seen groups like this when the barrel gets hung up in the stock in one position while shooting and then bounces to another position
460 magnum
Well-Known Member
I had a Rock River AR that would print groups like this.
Jon Bischof
Well-Known Member
Yep, I see this as a sign of warm barrel/pressure point on stock. Now it may not be that, but if you can't slide a pretty thick card between barrel and stock, it may be binding when warmed up.
piute
Well-Known Member
Could be scope parallax !
066wally
Well-Known Member
I hate these groups! Especially when shots 1and 3 are together and shots 2 and 4 are together.
Was said earlier but the couple times I had a rifle consistently throwing wonky groups like that, the stock was hitting the barrel. One was putting pressure on the barrel due to a slotted recoil lug pocket and the stock got put on the rifle torqued. Another that would throw them left/right where it'd almost look random (<3/4" vertical, 6" wide), but I was so frustrated I shot like a 15 shot group and it ended up looking like 4 sub groups spread over the 3" left/right of my point of aim. Ended up being the stock flexing under recoil and smacking the barrel.
I guess some details would help!
It's a 30 06 tikka t3x superlite stainless barrel synthetic stock. I used a Dremel to remove extra stock material around the forearm to give it extra float. I can slide several dollar bills all the way back to the receiver without hitting anything.
Strangely it does seem that it's shots 1&3 and 2&4 grouped together more often than not. This group was part of a load development set. The way I'm doing these is I'll shoot one Rd of each load, 5 different loads. The order is 1 to 5, 5 to 1, 1 to 5, 5 to 1. I started doing it this way because I would do each as a 5 shot string giving a 5 minute break between to cool. Now I just do 1 shot every 3-4 minutes and that's adequate to just keep the barrel warm. Again, I have had these groups before and after changing shooting patterns.
I do handload. Here's what they are:
Winchester brass, 3 firings, not annealed
Fed gm210 primers
H4350 (63.0gr)
Sierra pro Hunter 150gr
Started using my hornady comparator to get all my seating depths the same. So for these, they're all seated to be 2.731 base to datum, +/- 0.001
My rest is a Caldwell rock Jr and the bunny ear rear bag. I modified both to give a much more firm grip on my stock and be much more stable. These groups would happen before I did that though.
I don't have a good cheek weld because my scope is sitting too high... Therefore I sometimes find it hard to duplicate the amount of downward pressure I'm placing onto the stock at the grip.
Here is a few targets
It's a 30 06 tikka t3x superlite stainless barrel synthetic stock. I used a Dremel to remove extra stock material around the forearm to give it extra float. I can slide several dollar bills all the way back to the receiver without hitting anything.
Strangely it does seem that it's shots 1&3 and 2&4 grouped together more often than not. This group was part of a load development set. The way I'm doing these is I'll shoot one Rd of each load, 5 different loads. The order is 1 to 5, 5 to 1, 1 to 5, 5 to 1. I started doing it this way because I would do each as a 5 shot string giving a 5 minute break between to cool. Now I just do 1 shot every 3-4 minutes and that's adequate to just keep the barrel warm. Again, I have had these groups before and after changing shooting patterns.
I do handload. Here's what they are:
Winchester brass, 3 firings, not annealed
Fed gm210 primers
H4350 (63.0gr)
Sierra pro Hunter 150gr
Started using my hornady comparator to get all my seating depths the same. So for these, they're all seated to be 2.731 base to datum, +/- 0.001
My rest is a Caldwell rock Jr and the bunny ear rear bag. I modified both to give a much more firm grip on my stock and be much more stable. These groups would happen before I did that though.
I don't have a good cheek weld because my scope is sitting too high... Therefore I sometimes find it hard to duplicate the amount of downward pressure I'm placing onto the stock at the grip.
Here is a few targets
Attachments
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BrentM
Well-Known Member
My opinion is trigger control. Video yourself shooting. I've helped several students address this as they tend to pull up on the trigger since they are gripping the stock.
The last target seems you found something at 57.2 and 57.8. It's hard to say what's causing this but you are experiencing this during load development which makes it even harder to put a finger on. You mention having issues with cheek weld so I would start there as you already know it's a issue. I find it very frustrating not having a good eye view because your scope is too high and in my opinion it's probably the issue as your constantly adjusting your head, neck, etc... and as you shoot longer fatigue then enters the game even more than normal. Either change to lower rings or get a cheek rest that allows you to remain consistent. I've experienced cheek weld issues and simply put a cheek rest/ammo pouch on my rifle which has eliminated my issue on a couple of rifles. See my pic for the cheek rest I use. It has Velcro straps that can be put inside to raise or lower the amount of height you want. It works great for me. Good luck and let us all know what you find!
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