Advanced Marksmanship Help with groupings/ID fundemental errors?

[Vandy321]

Posted this on a BR forum, wanted to see what the hide had to say from the .30 cal guys.

2 pics below, 2 x 3 shot groups at each target. 500 and 700 yards. Rifle is a 300wm shooting 215 hybrids at 2988

It's a good load, ES of 9 and SD of 3.5, so I'm not thinking that's the problem. Steady full value 10mph wind today, but it was steady as it gets.

Have a few questions/thoughts. 2 distinct groupings mixed from 6 shots. The higher impacts are more in line with what AB is calling for elevation.

I dont think they were flyers, it's too consistent of locations to be that. My guess is (and I can feel it sometimes) my POI is impacted by how much I load (or dont load) the bipod. Didnt take notes on which ones went high. But based on 2 distinct POI's of low/right and the others more on elevation, but left....is this just a fundenentals issue?

At that range would a little less loading (more free recoil) cause a big enough dip in velocity to impact low like that? If I remember correctly the upper impacts had more of a load on the rifle, but really cant say for sure.

Anyt thoughts? Is this a fundamentals issue? If so, which is correct/more consistent with POI/velocities the firmer bipod load or the softer bipod load?

My 3 shot zero to start the day at 100 was sub .5...and the 2 different POIs if I measure them seperately are holding to that...figuring it's got to be my lack of consistency?

 

[Dthomas3523]

Could be several things or could be a combination of things adding up.

Assuming you have most things in order, vertical is largely affected by breathing and lateral is trigger control.

Bipod loading is only enough to take the slack out. But if you are loading pretty hard sometimes and then not loading at all, that could cause some vertical stringing. The velocity could change and the butt is dipping before the bullet is out of the barrel causing high impacts. Or when you’re loading hard, you have a flinch and driving the muzzle down prior to bullet leaving.

I’d start by shooting all shots the same way and document each group. Then go from there.

If you’re loading/not loading and it’s not grouping, look into your breathing or possibly flinch.

If you get two different and consistent groups with load/not loading, then you’ll know that’s the actual reason.

I’d shoot more and take better notes of each shot and go from there.

 

[Jack Master]

Here is my 2 cents. Take them or leave them. These are all dependent on you and your rifle set up. Since you didnlt share what rifle and stock you are shooting I've made assumptions.

Your photos make it look like these groups are about 4-5 inches apart. At 500 and 700 yards that is still less than 1 moa. What is the real number?

Fundamentals checklist
1. Parallax - Are you shooting a scope with adjustable parrallax? if its not adjusted for the distance this could happen.
2. Cheek weld - are you picking your head up between shots to run the bolt? If so, don't. Keep your face in the gun.
3. Sight picture - are you looking straight through the scope every time? if you're breaking your cheek weld you might be changing your sight picture.
4. Sight alignment - was there any mirage while shooting? could you have been aiming at 2 different spots that looked the same due to mirage? You barrel might be heating up and causing mirage in your scope.
5. Scope power - are you on max power that could make mirage worse? Dial it back to 10x then shoot.
6. Bipod load - this can change your POI if you sock has any flex in it. A cheap plastic stock will flex more with more bipod loading, this points the barrel higher in loading and when its suddenly unloaded by firing the rifle the barrel will drop. iF you have a rigid chassis this might not be the case.
7. Breathing - if 2 shots are taken at the bottom of a breathing cycle and 3 at the top or in the process you could get this to happen.
8. Trigger control - Are you slapping the trigger? Some people have elevations issues from slapping.
9. Recoil management - I am assuming these were shot prone - did your shoulder eat the recoil the same way everytime? was your shoulder relaxed for a couple shots then tensed up for a couple as the recoil started to get to you? tense shoulder will send rounds high. is the rifle hopping during recoil and making your should weld different for the next shot (in other words - did the rifle walk away from you )
10. Recoil management - are your straight behind the rifle with the but stock pulled to the center of your body? my but pad is typically on my collar bone. If you are bladed from the rifle the recoil can cause this, if your out on your deltoid way out in the "shoulder Pocket" you might be handling recoil different.
10.A - Are Your Flinching!

Equipment checklist
11. Something loose - are all of the screws in your scope, mount and rifle tight? I have had this happen then the action screw were not tight to spec.
11.A. is your scope reticle moving? could a piece of glass be loose in your scope?
12. Stock - if you have a cheap plastic stock if it flexing under recoil right where your trigger hand grips the rifle? Cheap hollow plastics are notorious for this. - better recoil management can help reduce the effect of this.
13. Reloads - could slight neck tension differences do this? - Were all the the brass then same brand and water Volume?
14. Chamber-ing - Did you cook the rounds in the chamber before firing? (heat them up with barrel heat) This can cause high impacts.
15. Barrel - How many rounds are through the rifle and how long has it been since cleaned? I had a carbon ring build up right in front of the chamber in one of my rifles and I started getting 3 groupings.
16. Barrel - is this a thin pencil hunting barrel? is it getting hot and walking after 3 rounds?

Want me to keep going? To get better answers we need better information. Rifle - scope- mount- position - bi-pod bi-pod mount. stock - chassis - time of day - weather - first born's name. To fix most of the issues above is getting experience and maybe taking a class.

Hope this helps, good luck.

 

[Vandy321]

Awesome checklist! Will learn it and run it next time im at the range. I'm decent with all of the above, but I'm sure something is off...this will be good to run through until it all becomes second nature

 

[M8541Reaper]

Awesome checklist! Will learn it and run it next time im at the range. I'm decent with all of the above, but I'm sure something is off...this will be good to run through until it all becomes second nature

Record yourself at various angles for each grouping. Compare the videos and look for inconsistencies or errors in the fundamentals. Are your fingertips white as you watch your entire hand flex/grip the rifle moments before firing? Play it a few times and zoom in on certain parts. Thumb in the same spot each time? Movement in the shot before the shot breaks? Is it a consistent 90 degree press straight to the rear or is it up and/or angled? Etc. video recording with your phone propped up next to you is the best way to review your performance.

Also, rip your scope off and check your scope base screws. Check all of your torque values and place witness marks on all screws. This will help and keep you in check during pre and post range maintenance/checks. Like an asshole, I failed to routinely check my base screws and went a long time without doing so...sure enough I started having fliers. Three stacked and then two stacked off the group. Consistently shifting. I got pissed at myself when I realized what had happened.

Note: if you have a set of quality rings, you shouldn’t have to worry about POI shift from removing the scope. However you should also be shooting a zero reconfirm when you get to the range and never leave without confirming zero. One thing I always recommend is that people should test their own gear. Show up, confirm your zero, then remove/replace your scope 3-6 times and shoot groups after putting it back on each time. Look for patterns and it will bring you piece of mind later on if you ever have to pull your optic to check the witness marks/torque.

Best of luck!

 

[Rocketmandb]

Note that a low ES/SD does not necessarily equate to good groups.