Barrel Tuning your Rimfire Questions

[UglyBagofWater]

I have a question or two regarding barrel tuning (in my case, a Bergara B14r with a Harrel Tuner.

#1, I live in Ohio, and with daily temps rarely getting over 40 degrees now, will the low temps effect the grouping of ammo (Lapua Center-X in the lot that excelled in even slightly warmer temps) enough to make the tuning attempt irrelevant?

#2, would it be best to use the Hopewell Tuning Method at 50 yards or 100? At 50, my B14r with this lot of C-X shoots 0.3” groups consistently already. But at 100, wouldn’t wind drift be a factor that may give inaccurate results? We rarely have still days here.

Also, any advantage in using a 3 shot group with the Hopewell technique, rather than two?

Thanks for any input in helping make the best of my tuning attempts.

 

[littlesister]

I have a question or two regarding barrel tuning (in my case, a Bergara B14r with a Harrel Tuner.

#1, I live in Ohio, and with daily temps rarely getting over 40 degrees now, will the low temps effect the grouping of ammo (Lapua Center-X in the lot that excelled in even slightly warmer temps) enough to make the tuning attempt irrelevant?

#2, would it be best to use the Hopewell Tuning Method at 50 yards or 100? At 50, my B14r with this lot of C-X shoots 0.3” groups consistently already. But at 100, wouldn’t wind drift be a factor that may give inaccurate results? We rarely have still days here.

Also, any advantage in using a 3 shot group with the Hopewell technique, rather than two?

Thanks for any input in helping make the best of my tuning attempts.

Target grade lubed ammo doesn't shoot it's best below 50 degrees. The purpose of barrel tuners on 22lr is to eliminate or at least decrease verticle stringing. I would think colder temps would effect verticle while having little effect on windage. This would make tunning difficult. As to the Hopewell method. People try to modify it, myself included but I have yet to find a better method to tune. Read the procedure again. At this point in the process 2 shots are enough as you will be looking at the overall 10 shot group.

 

[snipes81]

I’ll comment on question #2. I went through this scenario with my b14r this summer and had similar concerns about 50 and 100. My range has 60 and 77 yd markers as well as 50 and 100. I couldn’t find the 77 yd holes that day so used the 60 with success.
Personally I’d fight the urge to try and tune in the cold windy winter weather. If you have access to a 100 yd indoor range that might be worth considerin.

 

[6.5SH]

If the ammo doesn't perform like the various biathlon loads in cold weather a soft insulated lunch pack and a Lifoam Hot 'n Cold Pak can help keep it warm.

 

[Just Chuck]

Watching. I'm going to repeat the Hopewell process - the first time didn't really get me results I was looking for. But in fairness, I re-read the method and I didn't do my best work there. I did shoot at 85 yards on a no wind morning - so will try that again.

 

[littlesister]

Watching. I'm going to repeat the Hopewell process - the first time didn't really get me results I was looking for. But in fairness, I re-read the method and I didn't do my best work there. I did shoot at 85 yards on a no wind morning - so will try that again.

A few more thoughts on tunning which I hope will help! These are mine and surely not etched in stone but they are based on years of experience. I only compete at 100 and 200yds but I always tune at 50 and sometimes even less. Simply because I'm a better shot at 50 than I am at 100 or more and outdoor conditions have less effect at closer ranges. Indoor is the way to go if you have ascess. I tune on a standard PSL target using the Hopewell method. Some barrels don"t respond well to tuners, espically short "less than 22in" heavy conture barrels. .850 to .90, 24 in barrels are the easiest for me to tune. I'm one of those that believes a tuned barrel is a tuned barrel no matter what range you shoot. If tunning is attempting to get the bullet to exit the barrel on a signwave node where the barrel is neither in a upward or downward movement then range has absolutely no effect on tunning a barrel. I do believe that bullet speed can effect a tune but the difference between say 1073 speed and 1060 is not worth the trouble.

 

[littlesister]

A few more thoughts on tunning which I hope will help! These are mine and surely not etched in stone but they are based on years of experience. I only compete at 100 and 200yds but I always tune at 50 and sometimes even less. Simply because I'm a better shot at 50 than I am at 100 or more and outdoor conditions have less effect at closer ranges. Indoor is the way to go if you have ascess. I tune on a standard PSL target using the Hopewell method. Some barrels don"t respond well to tuners, espically short "less than 22in" heavy conture barrels. .850 to .90, 24 in barrels are the easiest for me to tune. I'm one of those that believes a tuned barrel is a tuned barrel no matter what range you shoot. If tunning is attempting to get the bullet to exit the barrel on a signwave node where the barrel is neither in a upward or downward movement then range has absolutely no effect on tunning a barrel. I do believe that bullet speed can effect a tune but the difference between say 1073 speed and 1060 is not worth the trouble.

 

[Williwaw]

. If tunning is attempting to get the bullet to exit the barrel on a signwave node where the barrel is neither in a upward or downward movement then range has absolutely no effect on tunning a barrel. I do believe that bullet speed can effect a tune but the difference between say 1073 speed and 1060 is not worth the trouble.

And if tuning is attempting to get the bullet to exit the barrel on a rising slope of the sine wave where the barrel is in an upward movement then range has everything to do with tuning a barrel. In this case the goal is to achieve positive compensation which is when the fast round exits on a lower trajectory and the slow round is 'lobbed' at a higher trajectory and their POI is coincident. As littlesister chooses to tune there is no mechanism shrinking vertical but the tune is not range sensitive.

Both methods work in theory.

I live in northern Canada and shoot daily year round. It all works fine for me down to about -15c and -20C is pretty pointless. I have tuned with SK Standard Plus in freezing temperatures and shot my best results at -3C to -8C. That lot and tune would do sub .3 inch average for an 8 x 5. Those aren't amazing numbers but I had only shot for a year, I'm outdoors in the snow, Harris bipod and rear bag, and hey, that is not match ammo.

I am not sold on the Hopewell although I do use it. It isn't the first thing I try.

I've put some effort into trying to get a handle on tuning but don't claim any expertise at all. I am not in a position to lot test(the logistics of where I live) so I buy a case at a time. I tune for every case and then shoot for score. If I'm not getting the results I think I should I might throw out the tune, add some weight and retune.

I won't shoot Eley in the cold, I think SK/Lapua lube handles the cold better. I keep my ammo very warm. I have hot water bottles in insulated sleeves in a small cooler with towels filling up the extra space. My rifle leaves the house warm also. One thing about that, I get mirage off of the warm barrel. I've rolled a thin plastic placemat to make a tube that is essentially a 22 inch sunshade. But it is a mirage shade. Spiderman placemats look coolest.

You might not have to do that much to keep stuff warm. Mine is in a tarped sled behind a snowmobile so it's in the cold all the way.

 

[Just Chuck]

My rationale for shooting at 85 yards rather than at 50, is that since the objective is to identify the settings that produce the smallest vertical spread, then vertical spread would be more pronounced further out. I would expect more vertical spread at 85 yards that 50 yards; so the tightest vertical groups will be easier to find.

Errors induced by the shooter - poor trigger control, follow through, etc. is factor with either distance. Maybe this should be done in a Ransom Rest type device to reduce some variables. Or at least a lead-sled.

Gladly, I've never been to an indoor range. I hear some have a lot of fans moving air so it's not dead calm either. I don't know that, though.

 

[FromMyColdDeadHand]

How much does grip/pressure on the gun affect gun harmonics?? I’d think on barrel movement, not that much, but maybe on how the gun moves under recoil- which would be a bigger issue with something with more kick than a 22?

 

[Defender32]

I tune at 50 yds for my first test. I will pick out the best numbers and re test those at 100 yds. I will shoot 2 round groups and move after each shot group. The picture is of my Di Precision with EC Tuner. Picture is sideways. Making Bottom Left corner as it is pictured 00 on tune start.

 

[Just Chuck]

How much does grip/pressure on the gun affect gun harmonics?? I’d think on barrel movement, not that much, but maybe on how the gun moves under recoil- which would be a bigger issue with something with more kick than a 22?

Maybe not the harmonics, but...some argue that rimfire takes more precise shooting skills than center fire because of the length of time the bullet is traveling down the pipe. Rim fire is, say 1050FPS and center fire is nearly three times that speed - so less time in the barrel. Any break down in fundamentals will show up more on rimfire than it would on centerfire.

I'd like to take credit for this but I stole it from [email protected]

 

[CBeck]

Every time I see 2 shot rimfire tuner groups all I can think is I could shoot my rifle without a tuner and the target would look just like that.

 

[gkgeiger]

When I tuned my Holeshot tuner I shot a couple 5 shot groups at each setting unless they were really bad and then I only shot one. Two shots doesn’t do it for me.

 

[Williwaw]

When I tuned my Holeshot tuner I shot a couple 5 shot groups at each setting unless they were really bad and then I only shot one. Two shots doesn’t do it for me.

How many consecutive settings would you do this for and what distance does the weight travel over that setting range?
Thanks.

 

[Adam B]

Target grade lubed ammo doesn't shoot it's best below 50 degrees. The purpose of barrel tuners on 22lr is to eliminate or at least decrease verticle stringing. I would think colder temps would effect verticle while having little effect on windage. This would make tunning difficult. As to the Hopewell method. People try to modify it, myself included but I have yet to find a better method to tune. Read the procedure again. At this point in the process 2 shots are enough as you will be looking at the overall 10 shot group.

I find this to be the exact opposite. I shot Center-X all last winter and I did not change my zero at all and my gun shot consistently through a wide range of very low temps.

I even bought polar biathlon and ended up never using it.

 

[gkgeiger]

How many consecutive settings would you do this for and what distance does the weight travel over that setting range?

Thanks.

When I received my rifle from Jerry Stiller he said to start at 200 and adjust in or out as needed. I think I actually started at 180 and tested at 5 click increments. I think there are 20 clicks between 180, 190, 200. I don’t have that rifle with me here in Florida. Anyway if I started to see an improvement I would tighten up my adjustments till I found the spot. As far as distance traveled I have no idea.

 

[FromMyColdDeadHand]

Every time I see 2 shot rimfire tuner groups all I can think is I could shoot my rifle without a tuner and the target would look just like that.

I can feel what you’re saying. But I think the reality is that you’re shooting two shot groups, by the number of them, so that if there are trends they should show up. So the information is from the repetition of groups, not from an individual pair.

 

[Adam B]

Tuning on a 22 is a waste. Unless you have 10's of thousands of the same lot of ammo things will change drastically from lot to lot. I tried several tuners and just stuck with my suppressor.

 

[Spatcher]

Why wouldn’t one just re-tune between lots? It isn't a large expenditure in either time or ammo.

 

[Defender32]

Why wouldn’t one just re-tune between lots? It isn't a large expenditure in either time or ammo.

This is exactly what I do. The lot I am shooting now I have 1700 rounds left. Then ill start a 5K round case of the same type different lot. The tune shouldn't be much different. If I blow 100 rounds to verify that I am still good on ammo for the next season of PRS RF & NRL22 matches that I'll shoot.

 

[Williwaw]

Adam says it is a waste of time ... changes drastically
Spatcher says why not retune every time
Defender says retune every time and it isn't much different

Who's right ... they all are. Sometimes it changes drastically, sometimes not, you won't know if you don't try it yourself and when it is all said and done you might think it is a waste of time or not. All of this keyboard expertise has the same qualifier ... "It depends ..."

So to the OP, as with most things on most forums you are getting good ideas but not necessarily the final word.

 

[Defender32]

Adam says it is a waste of time ... changes drastically
Spatcher says why not retune every time
Defender says retune every time and it isn't much different

Who's right ... they all are. Sometimes it changes drastically, sometimes not, you won't know if you don't try it yourself and when it is all said and done you might think it is a waste of time or not. All of this keyboard expertise has the same qualifier ... "It depends ..."

So to the OP, as with most things on most forums you are getting good ideas but not necessarily the final word.

I can agree. You can only know what you rifle will do when you test it for your self. All we here can tell you is what has worked for us at this current time.

 

[FromMyColdDeadHand]

I don't have the time or patience to lot pick ammo, so I'll buy good ammo and tune the gun to it.

YEs, you are running ammo to tune it, but you as you run that process, you are also getting practice, and I plan on running my Labradar on those shots.

 

[obx22]

OP, I appreciate this thread as it caused me to research the Hopewell method and apply it to action screw tuning on my B-14R (I don’t have a tuner yet).
I had quartering 5+mph wind at 2:00 and rain at one stage of testing, temps 62-68F
I have swapped the steel barreled action over to Bergara’s BMP chassis, and noticed my groups were horrible at 45 in/lbs at the last match. I have to do this test again in better conditions and see if it’s the same or different for another type of ammo.

 

[grauhanen]

How much does grip/pressure on the gun affect gun harmonics?? I’d think on barrel movement, not that much, but maybe on how the gun moves under recoil- which would be a bigger issue with something with more kick than a 22?

That's a good question.

Rimfire benchrest shooters can be very fastidious when it comes to what might influence the performance when tuning a rifle.

In short, almost everything can affect how a rifle with a tuner can react together. And when the shooting is not BR, it doesn't get any easier or more straightforward.

BR shooters typically shoot "free recoil" style. They don't touch the rifle, except for activating the trigger. The trigger pull must be very low. By avoiding touching the rifle, BR shooters avoid inconsistent contact with it, such as that which can be caused by inevitably varying levels of grip or pressure on the rifle when holding it.

Some BR shooters say they find that tuner readjustment is necessary when they move the scope or change it.

The rest and how the rifle sits on it -- the contact points -- should be consistent every time the shooter wishes to use the same tuner setting.

Consistent ammo is a must for achieving a properly tuned rifle. Without it, it's very difficult during whatever method of tuning is used -- Hopewell, a modified Hopewell, or something else -- to be certain if the results downrange are the product of the tuner or inconsistent ammo.

A tuner will not make inconsistent ammo shoot any differently. It will remain inconsistent.

Is it necessary to adjust the tuner for different lots of good, consistent ammo? There are differing views on that among serious BR shooters. Many will say that once the best tune is found (there can be more than one), the tuner doesn't have to be moved. It will shoot all good ammo well. Of course, others will disagree.

Is it necessary to adjust the tuner for different distances? If the "positive compensation" theory of how a tuner works is accepted, then the answer is "yes". Many serious BR shooters who also shoot at 100 yards report that a good tune at 50 works at the longer distance.

In any case, anyone using a tuner for shooting at a variety of distances must hope that adjusting the tuner for different distances isn't required. If it were, it would be very difficult to make adjustments, especially if distances varied unpredictably.

A tuner is not a short cut or a solution for inconsistent ammo. The first best course of action for a shooter looking to get the best accuracy out of his rifle is to find suitable ammo. Random lots of expensive ammo, regardless of the name on the package, won't guarantee good performance. Getting a tuner to work effectively and consistently relies on using a rifle with ammo that's consistent and uses rests that don't appreciably change between shots.

Finding the best tuner setting on a .22LR rimfire rifle may not be as easy as many may assume. A very experienced and respected BR shooter who posts on many forums and does extensive testing in his own testing tunnel offers this observation about how difficult it can be to tune a rimfire rifle:

A word of caution. I've never found it as easy to tune a RF rifle as most would suggest it is. Fact is, I've yet to test a rifle in my ballistic tunnel that was truly tuned even when someone brings a rifle and is convinced it's tuned.

See https://www.rimfirecentral.com/forums/showpost.php?p=11089975