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  1. #1
    Join Date
    Apr 2005
    Location
    Exiled in Texas
    Posts
    7,441

    Default Always Test Ammo for Your Specific Barrel

    I believe that most people here are aware of the quirkiness of barrel harmonics, and realize that every gun will shoot different types of ammo with differing degrees of accuracy. So I'm writing this (a) for the new guys who are still getting comfortable with rifles, and (b) as an illustration and reminder for those of us who know but who sometimes get lazy and follow a rule of thumb rather than getting actual data from our own rifle. It's also a hard lesson to follow whenever ammo selection becomes lean, as it is in the current market.

    I've decided to pursue precision rimfire shooting. At the time that I made the decision, it was in part because my local range was limited to 300m. I want to learn more about dealing with wind, and shooting a centerfire rifle inside of 300m doesn't allow you to really experience the effects of wind. Rimfire is also fun, and quiet, and a great way to introduce new shooters to the art. I picked up a CZ455 Tacticool, installed a Timney trigger and larger bolt knob, and topped it with a Leupold MK4 3.5-10x. (I do have one significant complaint about the optic: it's not optimal for rimfire because I can't adjust the parallax down low enough, so targets inside of 50m are quite blurry.) I then went out and bought a smorgasbord of ammo. This is about half of what I sampled:
    CDC41246-1AE7-43A3-B05B-84938927CB71_1_201_a.jpg

    While many are drawn to rimfire because of the low ammo cost, that wasn't really my goal here. I was not going to be hindered by ammo price, and was willing to plunk down however much gold was required for the best ammo that Eley can produce. I started with some Gemtech subsonic ammo, not expecting much and not getting much. American Eagle was much the same. I felt compelled to try the Federal Match, which has never performed very well for me in any gun. It performed the same as it had in the past. The worst group that I produced was with RWS Rifle Match S, which gave me this at 50m:
    951C647C-148B-40BD-980E-BB100F590996_1_201_a.jpg

    Interestingly, the RWS Rifle Match (no "S") was the number two finisher, with a .466" group at 50m.

    The surprise winner was the Norma Tac-22, which turned in a .343" group. This is ten shots at 50m:
    157186B7-353A-413B-9F8D-9D3E50752A0B_1_201_a.jpg

    The Midas+ (literally named for gold) runs about $0.50/rd and produced a ho-hum .706". My expectations for this ammo were high.

    I shot everything in one day, to ensure consistency. Same range, same weather, same gun, same mediocre shooter. I shot all of the cheap stuff, that I predicted would not be terribly accurate, first. That way, the gun was nice and dirty for all of the real contenders.

    I'm pretty happy that this gun prefers the $0.07/rd Norma Tac-22. I'm even happier that I bought a 5k case right before the shelves were emptied. I've had a few guns that oddly prefer the cheaper ammo. My Sig 556 shoots more accurately with M855 than it does with the 69 or 77gr match ammo. My SCAR17 shoots M80 ball almost as accurately as it does the 155gr Palma, and both are far more accurate than the 168 or 175gr match.

    You can start your testing with an educated guess based on barrel twist rate, bullet weight, and ballistic coefficient. But you have to actually get out and test the ammo in your gun to know how it will shoot. And for a valid comparison, you need to control for as many variables as possible. Ideally, this testing will occur before you select an ammo and stack it deep.
    Virtute et Armis

  2. #2
    Join Date
    Nov 2010
    Location
    South-Central Idaho
    Posts
    3,223
    Barrels are funny. I have a 6.5 Creedmoor that absolutely adores cheap Sellier & Bellot ammo. Shoots it much better than any match stuff Ive tried.
    Wanna Learn about Medicinal Herbs & Edible Plants?
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  3. #3
    Join Date
    May 2006
    Location
    NWFL
    Posts
    16,408
    I have a cz452 that I purchased about 2002 and added a timney trigger to. On the CZ452 and JW15 chinese copies, the barrels are not bad and triggers are terrible.
    Your worst group at 50 yards would mostly kill a squirrel with a headshot and practical killing of things is my primary interest. I use exclusively .22 LR segmented quiet ammo from CCI, 40 grains at about 700 fps in the longer barrel for one reason. It intended kill squirrels in a discrete manner and if I aim precisely at 75 ft to make a good shot, the squirrel dies (Squirrels do a lot of damage and it is legal for me to kill them). It is about a quiet as typical pellet gun, is more lethal, and the low velocity limits its range. But anyway I use a live oak as back stop to an ear of corn fixed in the tree directly in line of sight from a kitchen window.
    The trigger is more important than one hole groups relative killing when it is one shot-one kill.

    Relatrf subject shift: That is what I like about the AR compared to just about any other fighting rifle. For $80 from LaRue you can put a crisp 4 lb or less trigger on the gun. If you pay more I understand you can get it even lighter from others. If one wishes to shoot at long distance, of course get a quality barrel that is free floated, proper chamber, etc, and the best trigger you can get. Also choose the ammo that gives you the results that you want with your gun. After the trigger, the next thing is the best optic for what you are going to be doing.
    I have a 6.5 grendel 18 inch barrel and I have not made up my mind for the optic. I want that gun set up to be optimal for ranges of under 100 yards, but yet be capable of head shooting a goblin at 600 yards. At the moment I am on AR pistols in 300 blackout and 7.62x39. When I get those figured out I will return to the 6.5 g that is on an Alexander upper.

  4. #4
    Join Date
    Oct 2010
    Location
    Texas
    Posts
    125
    Years ago I assembled a custom 308 bolt rifle with a heavy bull barrel. I went to the range to sight in and have a little fun at longer range. I brought @ 100 rds of commercial 147 grain range ammo just to do preliminary sight-in and function testing. Boy was I disappointed! Shooting at 50 yds my target looked like it was hit by a shotgun. I have several 308's, both bolt and AR types and never had that bad a result. I then loaded with some 168 Federal BT rounds and what a difference. Literally one hole group at 50 yds and perfect cloverleaf groups at 100. The barrel is a 1-10 twist, but it'll only shoot 168 grain and heavier quality ammo. I tried 150 grain SP hunting rounds of various types and no go. So lesson learned, some guns are just very finicky at what they like. I have other 308's with the same barrel twist that seem to shoot just about any weight/brand. I still have this rifle and fed the proper ammo, it will outshoot most of my other rifles.
    Cranky Old Guy

    NRA Life Member
    GOA Life Member
    Army Jan 73 - Dec 79

    "We don't want yellow cowards in this Army. They should be killed off like rats. If not, they will go home after this war and breed more cowards. The brave men will breed more brave men. Kill off the Goddamned cowards and we will have a nation of brave men."

    In case of doubt, attack.
    ― George S. Patton Jr.

    "If the government is the answer, then the question is stupid!"

  5. #5
    Join Date
    Apr 2011
    Location
    Southeast United States
    Posts
    868
    Quote Originally Posted by LawDog View Post
    I believe that most people here are aware of the quirkiness of barrel harmonics, and realize that every gun will shoot different types of ammo with differing degrees of accuracy. So I'm writing this (a) for the new guys who are still getting comfortable with rifles, and (b) as an illustration and reminder for those of us who know but who sometimes get lazy and follow a rule of thumb rather than getting actual data from our own rifle. It's also a hard lesson to follow whenever ammo selection becomes lean, as it is in the current market.

    I've decided to pursue precision rimfire shooting. At the time that I made the decision, it was in part because my local range was limited to 300m. I want to learn more about dealing with wind, and shooting a centerfire rifle inside of 300m doesn't allow you to really experience the effects of wind. Rimfire is also fun, and quiet, and a great way to introduce new shooters to the art. I picked up a CZ455 Tacticool, installed a Timney trigger and larger bolt knob, and topped it with a Leupold MK4 3.5-10x. (I do have one significant complaint about the optic: it's not optimal for rimfire because I can't adjust the parallax down low enough, so targets inside of 50m are quite blurry.) I then went out and bought a smorgasbord of ammo. This is about half of what I sampled:
    CDC41246-1AE7-43A3-B05B-84938927CB71_1_201_a.jpg

    While many are drawn to rimfire because of the low ammo cost, that wasn't really my goal here. I was not going to be hindered by ammo price, and was willing to plunk down however much gold was required for the best ammo that Eley can produce. I started with some Gemtech subsonic ammo, not expecting much and not getting much. American Eagle was much the same. I felt compelled to try the Federal Match, which has never performed very well for me in any gun. It performed the same as it had in the past. The worst group that I produced was with RWS Rifle Match S, which gave me this at 50m:
    951C647C-148B-40BD-980E-BB100F590996_1_201_a.jpg

    Interestingly, the RWS Rifle Match (no "S") was the number two finisher, with a .466" group at 50m.

    The surprise winner was the Norma Tac-22, which turned in a .343" group. This is ten shots at 50m:
    157186B7-353A-413B-9F8D-9D3E50752A0B_1_201_a.jpg

    The Midas+ (literally named for gold) runs about $0.50/rd and produced a ho-hum .706". My expectations for this ammo were high.

    I shot everything in one day, to ensure consistency. Same range, same weather, same gun, same mediocre shooter. I shot all of the cheap stuff, that I predicted would not be terribly accurate, first. That way, the gun was nice and dirty for all of the real contenders.

    I'm pretty happy that this gun prefers the $0.07/rd Norma Tac-22. I'm even happier that I bought a 5k case right before the shelves were emptied. I've had a few guns that oddly prefer the cheaper ammo. My Sig 556 shoots more accurately with M855 than it does with the 69 or 77gr match ammo. My SCAR17 shoots M80 ball almost as accurately as it does the 155gr Palma, and both are far more accurate than the 168 or 175gr match.

    You can start your testing with an educated guess based on barrel twist rate, bullet weight, and ballistic coefficient. But you have to actually get out and test the ammo in your gun to know how it will shoot. And for a valid comparison, you need to control for as many variables as possible. Ideally, this testing will occur before you select an ammo and stack it deep.

    Excellent stuff! I need to pare down my ammo selection and do just as you say, test it, make a decision and stack it deep.

    My standards aren't as stringent as some. I have a friend who is obsessed with taming the barrel harmonics of his rifles; he's got a nice collection of targets showing variations of each load, listing 7.0 grains of this powder, 7.4 grains of that, 7.6, etc. I have to salute his dedication to the craft.
    Redneck Zen
    "Be careful what you get good at."

  6. #6
    Join Date
    Jan 2014
    Posts
    1,264
    Yup. Similar testing showed my Kimber 22 to like Wolf Match Target over anything I had from Eley (tenex, mainly, if I recall)

  7. #7
    I know many of you know this, but for thosr that dont...Same ammo but different lot numbers can produce different numbers. Case in point Federal Gold Medal Match 308 168 gr almost 1/4 difference at 100 yards. I load my own but If I shoot factory I will confirm zero with every different lot.

    Sent from my SM-G973U using Tapatalk

  8. #8
    Join Date
    Aug 2008
    Location
    Richmond, VA
    Posts
    2,402
    That used to be one of my biggest gripes about gun forums, "Hey, new guy here, what ammo shoots best in my new rifle/handgun?" I'm getting old/tired enough I don't usually even click on those threads anymore.

    I have an old Win. M52B that shoots amazing groups with Remington Thunderbolts, or did with the Thunderbolts made in the 70's and 80's.

    Buy a box of several different brands/bullet types/weights and try them out. Your rifle/handgun will "tell you what it likes." Both for functioning and groups.

  9. #9
    Join Date
    Nov 2018
    Posts
    763
    When in doubt, check your zero with new ammunition. Nothing shoots the same.

    Great summary of your process, LawDog. I do some instructing with the Appleseed Project on occasion; I may save your approach as a model to recommend to new shooters who aren't sure what to get. My recommendation is always "CCI Mini-Mag, 40-grain, but try several things and see what your rifle likes." Great example of that here.

  10. #10
    Join Date
    Feb 2011
    Location
    Central Texas
    Posts
    1,371
    My .22 shoots Win Expediter the best followed by CCI. Makes a huge difference for hunting.

    jim
    2 Samuel 22; Psalm 139:21-22

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