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OCW testing FAIL

rjacobs

Sergeant
Full Member
Minuteman
  • Mar 10, 2013
    2,231
    1,963
    So I was all excited to go shoot my first real precision loads using my new precision reloading equipment through my first real precision gun. What a frustrating day at the range I had though.

    Rifle:
    Remington 700 AAC-SD .308 in the stock piece of flexible shit Hogue stock, Timney 510 trigger, AAC 51t muzzle brake, Harris 6-9 swivel/notched/pod-locked, red tac gear rear bag
    Vortex Viper PST 6-24x SFP, Badger 20moa base, Badger medium rings

    I loaded 2 bullets today to test. I shot about every 30 seconds so the barrel should have been a consistent temp. I shot 5 zero confirmation shots with Federal 168g SMK ammo. I did not adjust zero during the OCW shots, I took what I got based on the zero shots with the factory 168g SMK's.

    First load: 185g Berger LRBT, Reloader 17(40-44.5g in half grain increments), mixed brass(FL sized, trimmed, chamfered, debured, etc...), WLR primers, 2.800 COAL

    5 zero confirmation shots. Rifle shooting great. 40, 40.5 and 41g
    IMG_20130619_165025.jpg


    41.5, 42, 42.5, 43... 42.5 shows some promise...
    IMG_20130619_165205.jpg


    43.5, 44, 44.5... 44 shows some promise... Ignore the tear, I think it was a ricochet
    IMG_20130619_165322.jpg


    Cases start at 40g on the left and go to 44.5 on the right in half grain increments. I dont know what was up with those 3 primers, they had what looks like pin hole blow outs. I dont know if I didnt get them seated quite right, bad primers, or what the deal was. Had some slightly hard bolt lift at like 41, 41.5, and then again at the 44 and 44.5 loads, but no other pressure signs that I can see looking closely at the brass.
    IMG_20130619_165844.jpg


    Moved on to 175g SMK's, Varget(42-45g in .5g increments), mixed brass as above, 2.800 COAL, WLR primers

    42, 42.5, 43, 43.5... Right out of the gate 42 looked decent.
    IMG_20130619_165643.jpg


    44, 44.5, 45... 44 shows some promise and is one of the loads that everybody says just works.
    IMG_20130619_165656.jpg


    Fired brass. Again had 1 primer that had a pin hole blow out. Never seen this happen before. 42g on left to 45g on right in .5g increments. Never had a sticky bolt with any of these loads.
    IMG_20130619_165849.jpg



    So after being frustrated as hell with my OCW testing of two different bullets I decided I would throw the suppressor on the gun(AAC 762SDN-6) and just have a little fun and shoot the other 15 of my 168g SMK factory ammo.

    SON OF A BITCH THE GUNS A TACK DRIVER AGAIN(well sort of). I fired 5 shots at the bottom target, I THINK I dropped the 5th shot, but its possible it went through the hole with the other 3.
    IMG_20130619_165757-1.jpg



    So I dont know what to think. I kept thinking its the gun in the shitty hogue stock, but then it does stuff like it does with factory ammo. That proves that both the gun CAN shoot and I, in theory, can pull the trigger correctly some times. The bench I was on was not great, I would have rather shot prone, but where I went doesnt allow that. I kind of see where I THINK I want to focus with each load, but I think I am going to hold off on shooting any more through this gun until I can get it in a better stock to eliminate that variable.
     
    Last edited:
    With respect to your efforts and shooting ability, I believe you skewed the results using mixed brass. Different brands of brass have differing capacity. Try you test again using one brand of brass and I believe you will be delightfully surprised.
     
    Yea I didnt think to much about that. Was hoping it wouldnt make that big of a difference since I am not trying to hot rod these rounds up above the max book powder charge. I guess its one more thing to learn in the precision reloading game.
     
    +eleventy on using same headstamp brass, lest you be wasting precious components.

    And I'd definitely get a Bell & Carlson coming before expending more rounds with that piece of shit, crappier-than-Savage-Tupperware-for-forearm-flex Hogue.
     
    As mentioned above. Start with one brand of brass. I dont care for FC brass, seems to be real soft. Please try new brass, looks like some of your brass pockets are gone per the pictures. Retest and see what happens.
     
    And I'd definitely get a Bell & Carlson coming before expending more rounds with that piece of shit, crappier-than-Savage-Tupperware-for-forearm-flex Hogue.

    Getting a Rock Solid chassis if I can quit spending money on other stuff for one month.

    Please try new brass, looks like some of your brass pockets are gone per the pictures.

    At worst this brass was once fired so this was the first(second I guess) loading on it. I cant imagine primer pockets failing this quickly, but those couple pieces of brass will be tossed. I have personally NEVER seen primer failures like that before which is weird. It was like their was a defect in the primer cup that allowed a small stream of gas to blow out.
     
    There's a BIG difference between Winchester and Federal brass.

    If you go back and find the groups which were tight in spite of having both case brands in the mix, you've probably got a winning charge there. :)

    Dan
     
    I am going to completely redo the test with sorted brass, but I am going to just wait until I get a proper stock to take the flexible flyer out of the equation as its at least contributing a small amount to my issues.

    Ive got other guns to shoot and enjoy for the next couple months until I get a chassis.
     
    You cant mix that brass.... Also you might want to try a little bit different seating depth. Doesnt take much to make a big difference.... As just starting out dont dispare... It really is about trial and effort





    I am going to completely redo the test with sorted brass, but I am going to just wait until I get a proper stock to take the flexible flyer out of the equation as its at least contributing a small amount to my issues.

    Ive got other guns to shoot and enjoy for the next couple months until I get a chassis.
     
    Ive reloaded probably 25k+ rounds(which isnt much compared to some of you guys), but up to now its been high volume 9mm, 45, and .223 for plinking on a Dillon 550b. So this is my first foray into precision and I am starting with the .308. Ive been loading for 300blk for a while too, but thats not really a "precision" round.
     
    What distance for the shots? If @100yds/m your zero is worrisome... yes, better than the others but that rifle, even with that stock, should do sub-moa. That zero is even 1.5moa approx if these were taken at 100y/m.

    What kind of support, and wind were you shooting from/in?
     
    To expand: your 44g on 185s is much more impressive than the factory loads. Is it repeatable? Don't worry about centered on target, you can adjust that. If you can repeat that group, stick with it. That's your money load so far.
     
    You may want to ask yourself what is your throat length?? I've got the same rig and my loads are 2.945" and I'm not even near the lands. Also maybe your rig just doesn't like the 185's. try the 168 smk and that will tell you if you have a shooter or not. Remington ... In my opinion.... Is heads or tails these days.
     
    Wind was pretty negligible. The bench I was shooting from SUCKED. It was very short front to back so I had the bi-pod as far forward as I could get it and still get my rear bag to support the rear, but it was not ideal at all and my rear bag was kind of on the edge of the bench most of the time. I wasnt real happy with the position I was in the entire time, but it was what it was at the place I was shooting at. Would rather shoot at a different place, but its an hour drive away and I just didnt have the time. The shots with the can on it at the end were pretty good(or at least I thought they were pretty good) so I KNOW the gun is capable its just the idiot behind the gun that seems to be the problem. Although with how flexible this gun is in this stock, maybe shooting with the can on is the answer to keep things from whipping around to much and having the stock contact the barrel. I dont know.
     
    To expand: your 44g on 185s is much more impressive than the factory loads. Is it repeatable? Don't worry about centered on target, you can adjust that. If you can repeat that group, stick with it. That's your money load so far.

    I only had the 3 rounds loaded up. I might load a few more up, just takes a minute and try them out again.

    You may want to ask yourself what is your throat length?? I've got the same rig and my loads are 2.945" and I'm not even near the lands. Also maybe your rig just doesn't like the 185's. try the 168 smk and that will tell you if you have a shooter or not. Remington ... In my opinion.... Is heads or tails these days.

    This gun will be fed from an AI mag shortly which has a 2.850 max OAL limitation so I am working with this as my limitation when I am doing load development. I know the Rem 700's generally have a VERY long throat. The 185 Bergers are supposed to be VERY jump tolerant. The factory ammo I was shooting was 168 SMK's so they do shoot pretty good through the gun IMO.
     
    I really try to avoid saying these things.... But:

    Myself and two friends started with a similar setup.. they are much different now though, and our hogue stocks are no more. That rifle, in stock trim will shoot sub-MOA. Unless you got a lemon out of the factory, and if so you need to figure that out soon. Yes, you can make it much more accurate than factory, but @ 100 it should be plenty accurate if it is in spec.

    Find a place you can go prone. Hold a great hold. Then take a perfect super-slow trigger pull. If it is the same doing that correctly, it's the gun. If it isn't, its the puller or situation you have to shoot in otherwise.
     
    I have seen the gun put out awesome groups well under 1MOA. I mean today it put 4 rounds damn near into the same hole. Im not worried that the gun isnt a shooter. I do need to get it into a better stock though and that is my next purchase.
     
    I read no further than where you described your rifle.

    Why would you waste all that time and all those components on testing the rifle with the original POS stock? The barreled action is quite likely sub MOA but in that stock you'd be better off throwing the bullets at the target. I write from personal experience.

    Joe

    Sent from my SAMSUNG-SGH-I777 using Tapatalk 2
     
    I would make a couple suggestions, first use the same brass as already stated here. Also pick a powder, primer and bullet and stick with it until you can't get it to shoot. There are way too many variables here. So, decide which bullet you want to use and seat it to mag length or .010 from the lands and pick a powder and primer. Load up 3 of several charge weights and go shoot them with more than 30 seconds between them. This time of year I may go 5 minutes between shots (for ocw test) and I shoot round robin also. With 5-7 different charges you should find something that is better than the rest. Then you can verify it the next time you go to shoot. If it is just as good as the first time try playing with seating depth. my .02
     
    I only had the 3 rounds loaded up. I might load a few more up, just takes a minute and try them out again.



    This gun will be fed from an AI mag shortly which has a 2.850 max OAL limitation so I am working with this as my limitation when I am doing load development. I know the Rem 700's generally have a VERY long throat. The 185 Bergers are supposed to be VERY jump tolerant. The factory ammo I was shooting was 168 SMK's so they do shoot pretty good through the gun IMO.

    Got ya. Missed that part
     
    No offense 8nbait, but did you even read the first post? To many variables? Im loading 2 different bullets with 2 different powders and testing them completely separately, just happened to be on the same day. I am loading to eventual mag length restriction so both are loaded to the same 2.800 target COAL. And part of this process is to help me decide on which bullet I want to use eventually, or hell, have data for multiple bullets and powders. Not like I am just willy nilly putting loads together.

    I think my biggest issue as was pointed out is the different cases being used and I will correct that. My second issue is the barrelled action is in a wet noodle of a stock that needs to go. I think if I fix both of those issues I will have a shooter on my hands.
     
    Truth: those groups at 100yards are pretty rough. If you say it shoots one hole, then it shoots one hole....but by looking at your pictures I have a hard time believing the shooter or the ammo can do such an incredible feet even at 100yds. My shooting partner dropped his 700 .308 into a wood laminate, with NO pillars at all and NO bedding. That thing runs 1/3" with me behind it on factory loaded Federal 155 hpbt (black and red box). When he shoots it, it instantly turns from a sub 1/2 moa gun to 1 1/4 +. So keep in mind, yes, that stock HAS TO GO like stated, and yes, you have to get all same headstamped brass, and I would start using different primers as well. Whatever primer issue you have going on is extremely sketchy. Oh one more thing, ditch that sketchy bench you speak of. You have WAY WAY too many variables going on to do any sort of methodical load development.

    Good luck, and post up when your able to get your ducks in a row, because when you do, you'll love watching those groups shrink, and they will continue to shrink as you get more comfortable and cognitive of eliminating outside variables that effect accuracy of your rifle and load.
     
    Truth: those groups at 100yards are pretty rough. If you say it shoots one hole, then it shoots one hole....but by looking at your pictures I have a hard time believing the shooter or the ammo can do such an incredible feet even at 100yds. My shooting partner dropped his 700 .308 into a wood laminate, with NO pillars at all and NO bedding. That thing runs 1/3" with me behind it on factory loaded Federal 155 hpbt (black and red box). When he shoots it, it instantly turns from a sub 1/2 moa gun to 1 1/4 +. So keep in mind, yes, that stock HAS TO GO like stated, and yes, you have to get all same headstamped brass, and I would start using different primers as well. Whatever primer issue you have going on is extremely sketchy. Oh one more thing, ditch that sketchy bench you speak of. You have WAY WAY too many variables going on to do any sort of methodical load development.

    Good luck, and post up when your able to get your ducks in a row, because when you do, you'll love watching those groups shrink, and they will continue to shrink as you get more comfortable and cognitive of eliminating outside variables that effect accuracy of your rifle and load.

    The bench I have no control over. Its a Conservation Department shooting range about 5 minutes from my house. I didnt realize the benches were so shitty until I shot there today. Like I said the range I prefer to shoot(where I can shoot prone) at is an hour away and it just wasnt feasible to get out there today(or this week at all). I am also a novice LR shooter so I am sure my technique isnt the best.

    With the can on it, the last group I shot was 3 shots touching and then 1 below it(last picture bottom center target) and I believe I dropped the 5th off the bottom of the target. So by seeing groups like that I know the gun can shoot. There are also quite a few with 2 rounds touching, so again, I am pretty sure the gun can shoot and its not just dumb luck(well partially dumb luck anyway) that I am getting some decent groups out of it.

    I dont know whats going on with those primers, its weird. I have never seen that before. Anybody have any real explanation? I cant really believe the primer pockets are worn out on the second loading of the brass. All the Winchester was bought new and has been fired once, the Federal was all from factory ammo so once fired as well. I have .223 brass with 6 or 7 loadings and still tight primer pockets. I have not touched these primer pockets with a swager, reamer or anything else. Primers were Winchester LR which I know are softer, but its all that is available around lately. I dont feel like those little pin hole blow outs were pressure related because there were absolutely no other pressure signs associated with them. I dont know if the primer was damaged or possibly the primer pocket was damaged. Im going to punch the primers and take a look, but those pieces of brass are getting trashed.

    Overall I think there were a few factors against me, but I will work through them. If nothing else I got some trigger time and a learning experience of what not to do and what to fix for next time.
     
    Its sounds like you have several variables that you can address here. First, I agree with the above recommendations to stick with one brand of brass. I've been using Lapua brass for 3 different caliber rifles that I'm working with, including .308win, and have been very pleased with it. It costs a little more, but it is high quality and worth the extra cost to me.

    Another thing that is likely affecting your results is the fact that you're shooting off of a bench that you're not comfortable on. Go somewhere where you can shoot comfortably. Once you get the brass and bench variables out of the way, then you can chase the next variable if you're still getting groups like this. However, I think the fact that you were using mixed brass, shooting from an uncomfortable position and working with a new rifle are probably going to prove to be a big part of the problem. Once you put a little time behind the trigger with decent brass and a steady shooting position, I think you'll be pleasantly surprised with the improvement in your results. Maybe check and make sure your action screws are properly torqued too.

    If you are still getting poor results after making these changes, then you can go chasing after the next variable....perhaps having it properly bedded in a good stock. Just start changing what you can for now and go from there. Eventually, it will all come together!
     
    You must work up loads for different brass. I have blown primers out of brand new Nosler brass with loads developed with Winchester brass. Looking at the primers, if you're using CCI #34 primers keep in mind they are thicker skinned than normal and when you are flattening them, you do have pressure.
     
    Your problem with the primers...is the primer. Winchesters have been having that failure problem frequently lately...there have been several post on that problem on the site. Bad bunch of brass cups. Call the factory...they'll probably replace them.
     
    Your problem with the primers...is the primer. Winchesters have been having that failure problem frequently lately...there have been several post on that problem on the site. Bad bunch of brass cups. Call the factory...they'll probably replace them.

    good to know.
     
    rjacobs, you can't mix the brass! (Just kidding. I just wanted to pile on, since people think telling you that same thing 20 times will make it more clearer. Hopefully it is more clear now :))

    When you say factory 168 SMK ammo, what brand is it? My recommendation to go get a box of Federal Gold Medal Match in 168 or 175 grain and shoot 5 shot groups and see how it does. It should be under 1 MOA. My factory Remington 700 Varmint was shooting 2/3 MOA with it.

    That should be your baseline to beat. It took me a long time to build my own load that actually beat FGMM.

    Few tips
    - Ditch the bipod for now when you are testing. Use sand bags on the front. It is harder to shoot with bipods and it tend to enlarge the group.
    - OCW testing - you are not really doing OCW testing when your load increment is 0.5. The spread is too wide. It needs to be more like 0.2 or 0.3. Also, you are not looking for the tightest group when OCW testing. You are looking for the same POI. So your comment about certain grains looking more promising doesn't mean anything.
    - Did you clean your barrel completely clean before you did all this testing? Keep it thoroughly cleaned, use 2-3 shots to foul it up, and go from there. My factory Remington barrel starts to open up quite a bit after about 25 rounds.
     
    When you say factory 168 SMK ammo, what brand is it? My recommendation to go get a box of Federal Gold Medal Match in 168 or 175 grain and shoot 5 shot groups and see how it does. It should be under 1 MOA. My factory Remington 700 Varmint was shooting 2/3 MOA with it.

    That should be your baseline to beat. It took me a long time to build my own load that actually beat FGMM.

    Few tips
    - Ditch the bipod for now when you are testing. Use sand bags on the front. It is harder to shoot with bipods and it tend to enlarge the group.
    - OCW testing - you are not really doing OCW testing when your load increment is 0.5. The spread is too wide. It needs to be more like 0.2 or 0.3. Also, you are not looking for the tightest group when OCW testing. You are looking for the same POI. So your comment about certain grains looking more promising doesn't mean anything.
    - Did you clean your barrel completely clean before you did all this testing? Keep it thoroughly cleaned, use 2-3 shots to foul it up, and go from there. My factory Remington barrel starts to open up quite a bit after about 25 rounds.

    Was Federal GMM 168g SMK. That stuff shoots great so that proves to me that the gun can shoot and I am capable(some times) of pulling the trigger correctly.

    Not sure I want to ditch the bi-pod since that is how I will be pretty much always shooting this gun. I dont think the bi-pod was causing my issue. The bi-pod in this wet noodle stock I am sure wasnt doing me any favors, but I also dont know if sand bags would solve anything with this stock either.

    From what I have garnered about OCW testing was that you started at .5g increments and tried to find a node(or multiple nodes) where your groups tighten up and then go back and load around that "node" in .2g increments. Most of the initial OCW tests I see are done in .5g increments and then the second "tier" is done in .2g increments. Where you are looking for similar POI is in ladder testing, which this is not. Maybe I am confused on what I am looking for though.

    Barrel probably had 150 rounds through it prior to shooting this. Like I have been saying shooting the 168g SMK GMM through it shows that the gun has the potential to put out great groups. Good group with it before and good group with it after tells me its not the barrel being to dirty and opening up.
     
    1. No bipods WHILE testing. You can use it after that. It just makes it more accurate, so one less factor to worry about. I don't think you are the best shooter off the bipod (I suck at it too), so it should help, while you are doing load testing
    2. You are misunderstanding the parts of OCW - please read this OCW Overview - Dan Newberry's OCW Load Development System. Take smaller increments and look for same groupings or POI across three increments.
     
    From what I have garnered about OCW testing was that you started at .5g increments and tried to find a node(or multiple nodes) where your groups tighten up and then go back and load around that "node" in .2g increments. Most of the initial OCW tests I see are done in .5g increments and then the second "tier" is done in .2g increments. Where you are looking for similar POI is in ladder testing, which this is not. Maybe I am confused on what I am looking for though.

    Barrel probably had 150 rounds through it prior to shooting this. Like I have been saying shooting the 168g SMK GMM through it shows that the gun has the potential to put out great groups. Good group with it before and good group with it after tells me its not the barrel being to dirty and opening up.
    The OCW instructions are all in percentages (Back off 7-10% from max and load up in 2% increments). For a .308, that typically will be .2 to .3 grains apart. As someone pointed out, you generally want to look at the center of each group and find a series of charges that seem to group in the same relative spot. Once you identify the middle charge in that series, you can tighten up the grouping for that charge by adjusting seating depth. My guess (I could be completely wrong) is that you are adjusting the node with seating depth.
     
    Have we considered twist rate? Is the AAC a 1-12? If so it may not even shoot the 185's worth a crap to begin with.
     
    Your problem with the primers...is the primer. Winchesters have been having that failure problem frequently lately...there have been several post on that problem on the site. Bad bunch of brass cups. Call the factory...they'll probably replace them.

    Truth!

    I had the same problem with a batch of 2k Win LR primers I had purchased back in 2010 or so. About 9 failures like yours in 600+ fired. Contacted Olin Corp through their website and got a call a few weeks later. They picked up the tab to ship the 1300+ remaining primers back to them, then I received a full 5k of a new lot of primers a month later. About two months total, but they took care of me!

    I would contact Olin Corp ASAP!
     
    No offense 8nbait, but did you even read the first post? To many variables? Im loading 2 different bullets with 2 different powders and testing them completely separately, just happened to be on the same day. I am loading to eventual mag length restriction so both are loaded to the same 2.800 target COAL. And part of this process is to help me decide on which bullet I want to use eventually, or hell, have data for multiple bullets and powders. Not like I am just willy nilly putting loads together.

    I think my biggest issue as was pointed out is the different cases being used and I will correct that. My second issue is the barrelled action is in a wet noodle of a stock that needs to go. I think if I fix both of those issues I will have a shooter on my hands.

    No offense taken, and yes I did read the post that is why I spent my time trying to help you. Good Luck.
     
    Your problem with the primers...is the primer. Winchesters have been having that failure problem frequently lately...there have been several post on that problem on the site. Bad bunch of brass cups. Call the factory...they'll probably replace them.

    Truth!

    I had the same problem with a batch of 2k Win LR primers I had purchased back in 2010 or so. About 9 failures like yours in 600+ fired. Contacted Olin Corp through their website and got a call a few weeks later. They picked up the tab to ship the 1300+ remaining primers back to them, then I received a full 5k of a new lot of primers a month later. About two months total, but they took care of me!

    I would contact Olin Corp ASAP!

    Talked to a guy from Winchester today and he is sending a shipping label for me to return all the primers I have from this lot. Got to go see how many I have in my stash since he wants all of them back from this lot number.
     
    That's great news! Perhaps those primers were fouling up your results. I'll be interested to see how that rifle shoots after you get some good primers and brass to work with.

    I know you think that your stock may be suspect as well. I agree that the stock would be high on my list of things to investigate. I recently had a 338LM that was throwing shots similar to what you are seeing. At 100 yards, it would put 3 rounds through one hole and then 2 rounds through a second hole, with about 3/4 inch space between the two holes. The shots were not always consecutively through the same hole, it would often jump back and forth between POI. That crap was simply unacceptable to me! I tried everything I could think of to tweak my ammo and make that gun shoot. Finally, I took the rifle to a topnotch riflesmith who bedded the action into my Bell & Carlson and now that rifle is consistently shooting sub 1/2 inch groups. The difference in the way the gun shoots is night and day, so I'm a believer in bedding the action into a decent stock. Good luck with it and report back here with whatever happens next.
     
    I sorted all the brass today after punching 450 live primers. Have probably 80% FC brass, about 20 pieces of Hornady Match and the rest Winchester. I have about 1500-2000 more pieces of brass that I havent done anything(no brass prep) with I need to prep up and sort. I know I should have around 1000 pieces of Winchester since my old man bought 1000 pieces a couple years ago.
     
    Something I didnt see mentioned is,,,some powder (like varget) doesnt like to be shot over the top of another type powder.It may take 5-15 rounds down the tube for it to settle down and MAY skew your testing.Just thought it was worth a mention.YMMV
     
    I had the same results you posted...1.5-2.0 inch groups, gas leakage which probably eroded your bolt face, using mixed brass and WLR primers, RL 15 etc. Rifle is Savage model 10, .308, Brux barrel, accu stock and accu trigger, Vortex Viper 6-24 FFP not a real high end rifle. What I did: tossed the mixed headstamp brass and bought .308 Lapua brass, My Weigh digital scale, Sinclair tactical bipod, added lead to increase stock weight, changed the primer. I would have liked Federal Gold Metal primers but none were available so I used CCI 200 LR. Groups went from 5 shot groups of 1.5 inches to .75, usually all the bullet holes are touching at 100yards. The rifle will regularly hit a dime at 100 yds. Recently I've switched to a co ax press and sort the 168SMK bullets by ogive length. Read the stickeys on this site about reloading, it offers many tips on how to improve your reloading... because there is a big difference between precision reloading and "hunting" reloading. Hope this helps.
     
    Bingo, watching snipers on TV, something finally clicked with me. They do not break their cheek weld between shots. I finally realized that even with my 8.5-32x56 NightForce NXS scope, I was not completely getting rid of parallax shifts. When I started maintaining my cheek weld for the entire string, my group sizes improved.