Lapua lot testing and barrel wear question

[Tokay444]

Nope, doesn't show up like I expected it to, Tokay.
50, 100 and 200 yards.
Surprised the snot out of me.
As long as ammo quality was similar, so were the results.
I'm finding that cartridge quality has more effect than bullet velocity.

How can you expect consistent trajectories from hi-v 22lr,
when most of it looks like crap fresh out of the box.

How about 300 and 400?
What velocities are you seeing from your preferred HV ammo? Where does it go trans?

 

[Gleedus]

At 50 yard it could be that one is more accurate then another. Long range is my interest so that is most of my testing.
ES are not everything when is comes to long range yes I understand what the ballistics say and in general that holds true but.
I have a lot of Eley Force average ES of 57 shoot around 4" 20 shot groups at 200.
I also have a lot of Eley Contact that is ES of 25. Shoots 5" 20 shot group at 200.
50 yard accuracy for both is the same.
I have another lot of Contact thats running a ES of 48 and groups at 4.5" at 200.

I have a lot of tenex thats 65 es and a lot of center x thats in the 50s. They dont shoot at 200....

When comparing like ammo SK long range vs SK Rifle match or Eley Force vs Eley Contact or Federal Target SV vs Federal Target HV. The all shoot comparable to their counterpart at 200.

 

[justin amateur]

Tokay, had to grab my calculator.
40 grain 22lr plated round nose rated 1235 fps
goes transonic between 30 and 40 yards from the muzzle.
So any distance beyond 40 yards it's a subsonic projectile.
That is why cartridge quality and atmospheric conditions have greater effect.

 

[Tokay444]

Tokay, had to grab my calculator.
40 grain 22lr plated round nose rated 1235 fps
goes transonic between 30 and 40 yards from the muzzle.
So any distance beyond 40 yards it's a subsonic projectile.

Got any targets to post?

 

[justin amateur]

Targets to post? Didja hear that groan of dismay?
They know what's coming.

Oh yeah, lotsa targets.

Look at Eley Contact and Eley Force.

50 at 200

I think I've come up with a useful scenario...maybe. :rolleyes: 50 shots at 200 yards, rimfire, whatever setup makes you happy. 22lr, 17 hmr, 22wmr, 17hm2, 17wsm, all brands, all types. Full benchrest setup, bipod, bags or one-piece test rest, it doesn't matter. Grab a chunk of cardboard, about...

www.rimfirecentral.com

 

[Gleedus]

One day I did this

and then there was the time I did this

this one I was holding 1.6-2.2 mil of wind. So It might not count.

This is a small sample from my collection. I used to believe the transonic theory until I tested. It maybe true that the bullets are losing stability because they started off HV but if that doesnt affect the results on target I dont care.
When I started testing 22lr long range and trying different things out it shattered many of my preconceived ideas I learned on the internet. Now if I read a "rule of thumb" I dont believe it until tested. This can go into many things.

Long range 22lr consistency is an illusive goal. We can argue all day about what people say but go and try for yourself... That is the very reason I am currently testing barrel length and the effects on long range performance. I know guys personally who have done this and know of a few more that have. Most of the testing was done based on 50 100 yard performance. Not everyone came to the same conclusion. 50 yds is of little interest to me so I will be looking at 200 yds as my benchmark. There is another guy doing the same that I know.... just maybe we will have different results . But maybe.... Maybe I should do a thread like Justin does with his testing. But it seems like a lot of fuss for nothing. Easier just to do my thing and not share....

 

[Tokay444]

I live in the 519...

 

[Gleedus]

I live in the 519...

Hey maybe we shoot together one day! Do you shoot the PRS rimfire?

 

[Tokay444]

Not yet. Would love to start.
I shoot at Galt and Twin City.

 

[Gleedus]

Not yet. Would love to start.
I shoot at Galt and Twin City.

I shoot in a field! I'm hosting the April Northern Rimfire match so the PRS rimfire match. Sign up if you need gear for the first one that can be arranged. I will gladly mentor a guy for his first match!

 

[justin amateur]

Now if I read a "rule of thumb" I dont believe it until tested.

Yep, gotta agree with ya', C.
Too much of what has been claimed hasn't worked out as expected.
All too many of those supposed "rules" fall apart under scrutiny.

 

[grauhanen]

Long range 22lr consistency is an illusive goal.

Indeed. It's not only deceptive and illusory, it's also elusive, hard to achieve.

The rifle is the most straightforward part of the equation because it's not hard to identify good rifles. The more difficult parts are identifying the most consistent ammo. It's not always easy in some areas to be able to evaluate a sufficient quantity of good ammos to find the most suitable. Another difficult part is learning how to shoot according to the conditions. If all shooting could be done in conditions in which wind is negligible, it would be much easier to shoot more consistently.

 

[Tim7139]

I have tested the HV accuracy vs SV at long range. The HV version with the same bullet as the SV has shown same or greater accuracy at long range. Of course you can have lot accuracy variation skew the results so I did a couple different ammo and lots.

Now I have also seen loss of stability with SV ammo in cold conditions where the sound barrier was lower then velocity due to weather. But in all cases when I switched to the HV version of the same bullet the bullets regained stability. They still didnt shoot very well but no key holes. SV 12-14" group at 50 HV 2-3".

I have slowly come to the opinion that the HV vs SV is mostly rifle dependent and results are affected by standard lot variation.

Side note on air gauge with a proper fitting gauge you can find variations in bore diameter. Some day when your bored run one through a couple of Ruger barrels.

Spot on re the airguage, their single solitary use is to show bore variations which they do well. They have no capacity to “ measure” what those variations are only, “ it just got bigger”, or “it just got smaller” on a relative basis.

 

[Tim7139]

#1 all you said is I'm wrong. I actually have no problem with being wrong and learning.

#2 you understood the question even though I asked It wrong. Yet you didnt answer the question.

Actually I dont know that you understood the question but with all the knowledge you have accumulated over the years I expect you did.

#3 the first part of my question was about the carbon ring. Your "nice, direct, response" had nothing to do with a carbon ring which was actually the main part of my question.

#4 when I suggested with my "nice, direct, response" that you were not helpful you had to resort to name calling once again.

#5 you assume a lot as I am no longer a infant. Actually have a full time job already. Hard to believe but true.

You often bring up interesting points an comments to show other sides of discussions but too often you ruin a good conversation by your "nice, direct, response". Dont lose what little credibility you have left by getting tied in a knot when ever someone answers your "nice, direct, response" with a "nice, direct, response" in return.

All right let me circle back and try this again re #3. First off, OK I overreacted....my apology.
the primary reason I entered into this black hole is because in the first couple minutes when I hear a qualifier about the “ upper levels of rimfire precision” blah, blah, blah my little ears prick up.
within minutes there is ZERO evidence of higher levels of anything including the guns. They’re zero versions of higher level, sweet guns yes. Higher level to me boils down to custom equipment including barrels, and the ability to drive them and maintain them. There is more than a little misinformation around here are guys now spending serious $ on some offerings without any proper mindset about maintainance.
Now for the sake of argument the highest level out there is BR and position also using essentially the same SS match barrels.
If you’re using a SS match barrel, it is likely to be a taper lapped buttoned barrel....not always but most times.
Taper lapping has proven to be quite important for top accuracy in those barrels.
Now when you shoot lots of rounds, you barrel fouling doesn’t get progressively worse if you shoot high grade ammo because the drive band of the slug scours it down the pipe leaving a film of relatively clean, warm lube in it’s wake.
the issue is when the skirt of that slug which is often NOT lubricated, slaps into that leade and in a moderately short spat can leave lead as well as combustion carbon that can build in layers, become quite hard, and form a ring, often unevenly.
you’ve got .0001”-.0002” of taper in that bore. How much carbon/ lead has to build before it is gone....robbing barrel potential.
got it now ?

 

[justin amateur]

Air gauge video - I had to watch it again.
Yep measurements are relative to a known diameter.
Accuracy can be to 5 millionth's of an inch.
Good enough to measure wear differences over time, at any location in the bore
as long as you have the reference diameter to check to at each use.

 

[Gleedus]

Which would then allow you record the amount of bore diameter growth relative to the original ID.

 

[phlegethon]

I think some people in this thread may benefit from reviewing this:

 

[AGrizz]

Air gauge video - I had to watch it again.
Yep measurements are relative to a known diameter.
Accuracy can be to 5 millionth's of an inch.
Good enough to measure wear differences over time, at any location in the bore
as long as you have the reference diameter to check to at each use.

Precisely. Is measurable.

 

[LeftyJason]

Air gauge video - I had to watch it again.
Yep measurements are relative to a known diameter.
Accuracy can be to 5 millionth's of an inch.
Good enough to measure wear differences over time, at any location in the bore
as long as you have the reference diameter to check to at each use.

Which would then allow you record the amount of bore diameter growth relative to the original ID.

Precisely. Is measurable.

True it could be. Have any of you looked at how much they are?

Mahr Dimensionair Air Gage Dial type - Willrich

Mahr Federal Dimensnionair Air Gage Amplifier

willrich.com

You might want something closer to a 16000:1. That is $2373 just for the air measuring part.

Add in at a guess $500+ for the probe that actually goes in the bore. Add some more for the master. I don't know the shape the probe would need to be since it is rifled now. Oh and be good enough that you don't scratch the bore since the probes are steel and you want to be able to shoot it. You better have a highly climate controlled area as well. At the sizes these can measure hand warmth can matter.

Spoken as a person that has 3 2500:1's on the bench at work and sometimes uses all 3 on the same job.

 

[justin amateur]

Lefty...are you volunteering?

I did say it had to be someone who knew how to use one properly.

I attempted to slug the bore and measure my new barrel
first when received, then after 700 shots. But since the muzzle is
the smallest diameter and the spot that received the least wear
the difference in the 2 slugs was negligible. That could be due to caliper quality
or as you pointed out, thermal coeffecient of expansion.

 

[Gleedus]

Is the muzzle actually the smallest? Does CZ really check? Maybe they have a tapered mandrel?

 

[justin amateur]

C, I've slugged this barrel twice.
You an feel the resistance increase when the slug passes a rough spot
or tight section of the bore. Rough spots are almost gone, but I can feel
that resistance increase as the slug approaches the muzzle.
Most definitely smaller bore diameter at the muzzle.

 

[Gleedus]

Interesting. I've never slugged a bore. Never figured its worth it. Now I'm curious.

The IBI barrels are honed before rifling so I dont think I'd see anything.

 

[Tim7139]

Lefty...are you volunteering?

I did say it had to be someone who knew how to use one properly.

I attempted to slug the bore and measure my new barrel
first when received, then after 700 shots. But since the muzzle is
the smallest diameter and the spot that received the least wear
the difference in the 2 slugs was negligible. That could be due to caliper quality
or as you pointed out, thermal coeffecient of expansion.

Caliper???? How many errors can one human make??? How many guys here have actually slugged a barrel, the proper way, with a micrometer, using a proper slug to avoid errors[ you cannot use anything], also making sure while using the several slugs needed, you periodically reverse them or bump them up to check, and then make sure you finish my checking for a round bore at the muzzle ? Report back if/when you get proper slugs to measure and do 10-15 of them. You know what to look for on the slug, other than measurements right ? Oh, you got the barrel clean, right down to bare metal right? Properly lubricated it, lightly, right?
And FYI you can look at all the videos you want, as I said, air gauges are typically used to see interior variances, primarily during lapping.
Barrel interiors are established after drilling and/or reaming and usually checked with deltronic pins. You want to check barrels, buy a set from .2150" to about .222", make sure you get them in 1/2 tenths, prepare to spend well over $1000.

C.C. guy with the pie chart.

 

[justin amateur]

Mistakes? Years worth. That's how ya' learn.

Extra 10 or 20 grand in specialty tools ain't in the budget Tim.
Working with what I have and making no excuses.
I'm not stopping anyone from showing me how it should be done.
Sadly, it appears no one is willing to take the time or make the effort.

Tim, how about you doing a bore wear test.
Demonstrate how burn residue doesn't smooth out the rifling.
I'd be more than happy to see it done correctly.
As it is, seems I'm the only one willing to go through the process.

Y'all are stuck with my meagre efforts.

 

[AGrizz]

Caliper???? How many errors can one human make??? How many guys here have actually slugged a barrel, the proper way, with a micrometer, using a proper slug to avoid errors[ you cannot use anything], also making sure while using the several slugs needed, you periodically reverse them or bump them up to check, and then make sure you finish my checking for a round bore at the muzzle ? Report back if/when you get proper slugs to measure and do 10-15 of them. You know what to look for on the slug, other than measurements right ? Oh, you got the barrel clean, right down to bare metal right? Properly lubricated it, lightly, right?
And FYI you can look at all the videos you want, as I said, air gauges are typically used to see interior variances, primarily during lapping.
Barrel interiors are established after drilling and/or reaming and usually checked with deltronic pins. You want to check barrels, buy a set from .2150" to about .222", make sure you get them in 1/2 tenths, prepare to spend well over $1000.

C.C. guy with the pie chart.

Tim, Tim, it is very evident you have absolutely ZERO experience in an inspection laboratory or machining or being a Tool and Die Maker. So why dont you just go and curl up in the corner and keep your mouth shut.

Where you may be of some use is in your ability to shoot a rifle. Advise you try to stay on that course and leave the rest to people who know. Using a Deltonic Pin in a barrel is like sticking your dick in old Haggie from the east side.

You are trying to be something you are absolutely not and that is the rimfire genius God of all you surveil.

 

[justin amateur]

The rimfire genius God of all you surveil.

Snort! Sorry AG, but it wasn't so much what you said,
as that I heard it in James Earl Jones voice.

Echoes of Thulsa Doom, eh?

 

[Tim7139]

Tim, Tim, it is very evident you have absolutely ZERO experience in an inspection laboratory or machining or being a Tool and Die Maker. So why dont you just go and curl up in the corner and keep your mouth shut.

Where you may be of some use is in your ability to shoot a rifle. Advise you try to stay on that course and leave the rest to people who know. Using a Deltonic Pin in a barrel is like sticking your dick in old Haggie from the east side.

You are trying to be something you are absolutely not and that is the rimfire genius God of all you surveil.

Right.....that’s why a handful of the best rimfire smiths that ever drew breath use them on every barrel.
That’s why my smith, who has made more national championship, and world record 22 rifles Than you could imagine will not do a barrel without them. Among the reasons that many world class machinists are lost when it comes to RFBR.
C.C. You‘re like squad.

P.S. Just for shits and grins, have you ever, EVER, measured and fit a match barrel ?
I’d bet 5 grand right now, that’s a hard no.
PM me, I’ll give you Gordon Eck’s number, takes about 5 minutes to learn how smart you are.

Lastly, rimfire God, well no, but it does bring to mind a classic joke about the 2 guys hiking in bear country, one guy is super concerned about bears.....outrunning bears, etc, asked his buddy if he was “ faster than a bear”
Reply....well no...I don’t have to be faster than a bear, I just have to be faster than YOU.
This is kinda like that.

 

[LeftyJason]

Lefty...are you volunteering?

I did say it had to be someone who knew how to use one properly.

I attempted to slug the bore and measure my new barrel
first when received, then after 700 shots. But since the muzzle is
the smallest diameter and the spot that received the least wear
the difference in the 2 slugs was negligible. That could be due to caliper quality
or as you pointed out, thermal coeffecient of expansion.

Nope. Not volunteering. Don't shoot that much, don't have the money for the tooling, and can't take in to work. Defense sub contractor.

 

[grauhanen]

How much does a barrel "wear" after a case of ammo? After ten cases?

It's not something that will be clear by looking through a borescope because what it can reveal is limited. There may be signs that egregious imperfections in areas such as the leade wear after thousands of rounds. But a borescope doesn't measure anything. It produces no quantifiable information.

With regard to the bore, what's essential to accuracy are the characteristics that make each one unique -- the consistency of the rifling throughout, the concentricity of the bore through the length of the barrel, areas of the minutest tightness or looseness that remain after lapping -- typically remains unaffected by mere thousands of rounds of SV lead ammo. Bores potentially remain remarkably accurate for a long time. There are many examples of barrels on older rifles that still shoot very accurately even though they have shot many tens of thousands of rounds.

But since bores are unique there are no hard and fast rules as to when a barrel has reached the end of its life, when it has too much wear. What contributes to wear? According to Eley, there are numerous factors, including, primarily, how much it is used, whether multiple rounds are fired in quick succession, the type of ammo used, how the bore is maintained (an argument for cleaning regularly). Barrel life and wear: when should I replace my rifle? | ELEY

To return to the question above, how much does a barrel "wear" after a case of ammo? After ten cases?

It is very unlikely that shooters who are not top level competitors will discern any difference after 50 000 rounds. They may not see any appreciable difference even after double that amount. There's no rule of thumb except to note that a barrel is excessively worn when it no longer is as accurate as it should be. If it was a .5 MOA shooter at 50 and can no longer do that with lot tested ammo, it's time to replace it.

One of the problems for most shooters is that they don't really know how accurate their rifle ought to be. Of course, everyone would like a consistent .5 MOA shooter. But that's not going to happen with the majority of rifles, especially when they are shooting random lots of ammo, no matter what ammo manufacturer's name is on the box. It simply isn't the way they are supposed to be. To illustrate, the average CZ rifle, even those with the CZ "match" chamber, is an unlikely candidate for a .5 MOA rifle. CZ barrel quality is not consistent enough that the average CZ can ever shoot that well. Rifles that are .5 MOA typically have custom barrels and shoot lot tested ammo by shooters who are experienced.

Of course some may say that how a rifle performs at 50 yards is irrelevant to them because they shoot at four times the distance and more. The thing is that if a rifle can't perform well at closer distances, it doesn't bode well for their performance at longer ones. The reason for this is that .22LR accuracy doesn't improve with distance. There's no factory .22LR ammo that shoots better at longer rather than at shorter distances. On those rare occurences when a lot of ammo produces better results MOA-wise at a longer distance it's not because it's predictable or anticipated. The bottom line is that .22LR accuracy is not linear; it gets worse as distance increases. If a rifle can't shoot well with a particular ammo at closer distances, it's not going to do better further out.

There's a rule of thumb that Justin has used in this forum and elsewhere that shooters would do well to note, the half third rule. "The half-third rule of thumb. Under similar conditions, same rifle and shooter, at one half the distance expect one third the spread." Although Justin has said elsewhere that"The extrapolation in reverse doesn't work as well. The double triple rule. Time of flight and variations in wind not yet traveled through, can skew things badly." RimfireCentral.com Forums - View Single Post - group size comparisons at different yardages it would seem to make sense that as a rule of thumb that mathematically it must also work in reverse.

Regardless, the point is that .22LR accuracy is like getting old. People may like to think that things get better the further away one gets from the beginning ("things get better with age"). But it doesn't. Accuracy diminishes inexorably with distance, bodies get frailer with old age, and neither can defy that on its own.

 

[justin amateur]

Yeah G, half-third works but double-triple has problems.
Get those days where the wind effects vary along the projectile path,
especially when dealing with turbulence, my rule of thumb falls apart.
Looking at Eley and Lapua test facility results, the double-triple rule works.
Indoors, minimal atmospheric effects and the results correlate.

If I had access to better facilities, tools, measuring equipment,
I would have used them. I can see the wear taking place, figured out the cause,
understand the mechanical aspects of what is occurring, but no way to truly quantify improvement over time.
Such are the limitations of being an interested hobbyist.

 

[IdealJoe]

I'm not going to try to convince anyone here of anything. But - I have a strong background in centerfire benchrest, gunsmithing, precision machining and metrology. Most of what Tim has been saying is a matter of fact. I understand the passion of chasing a set of beliefs to the end and I am a skeptic to the core. Just know that others have chased these same theories over and over and over. Some things can be considered settled science such as trying to gain meaningful measurements with an air gage in a rifled bore.

Regarding the accuracy of a CZ. Myself and some friends just bought three 457 varmint trainers with the Manners stock. We have a 50 yard indoor range. We all are shooting the one lot of Center-X we could find. The best rifle averages in the mid 3's. The worst is mid 4's. A .5 or larger is rare with any of them. The only thing done to them is a trigger spring change. I am quite impressed with what the borescope shows me for the barrel and chamber quality. CZ appears to have their act together with these.

Love to see the passion you have Justin. I enjoy reading your tests.

 

[justin amateur]

I'm easily entertained IJ.
Question everything, find out what works and what doesn't.
Right or wrong in my methods, I'm having a good time.
Sometimes I even learn something useful.

 

[AGrizz]

Tim Tim Open Mouth and insert foot. This may get you started if you have the ambition. I am not here to try to impress you or anyone else here. This settled science and fact that all refer to is straight out horse shit.

Try to start here and I can keep you going if you wish. https://metrology.news/integrated-in-process-bore-gauging-for-cnc-machine-tools/

 

[Tim7139]

Tim Tim Open Mouth and insert foot. This may get you started if you have the ambition. I am not here to try to impress you or anyone else here. This settled science and fact that all refer to is straight out horse shit.

Try to start here and I can keep you going if you wish. https://metrology.news/integrated-in-process-bore-gauging-for-cnc-machine-tools/

Well, still waiting for your answer about personal experience measuring match barrel blanks.
Guess I wait a while because it seems that would be ZERO.
Ever seen one?
Ever seen one fit?
Been inside or within 10 miles of a barrel shop?
Yeah, I though so.
Dif between me and you......I have the creds to back it up.
you never took me up on the phone #, I’m guessing because you don’t have a clue who the guy is do you?

Nice site by the way. You do realize the topic is RIFLE BORES don’t you Forrest?
Turn around.........look at the pretty bear.

 

[Gleedus]

Tim your last statement would make some wonder. It could be true then again it might not. Online anyone of us can say anything. Some people say a lot others others try to show what they have observed.
You obviously know something of rimfire as the comments you make it wouldnt be possible for you to pull out of your ass without knowing something about this gig.
Your last reply regarding #3 was good and informative. We could say close to the peak of the pie.
I have been doing some testing of my own regarding cleaning and the carbon ring. Results have been interesting. I have not recorded accuracy differences yet.... BUT I have a rifle that when colder then -8⁰c to -10⁰c there was 1 ammo that would lose stability and key hole. I cleaned the carbon ring and it seems that fixed the stability issues. Now I only had 1 cold day and it was barely cold enough to be absolutely sure that all stability issues are corrected. That topic will have to wait until next winter unless it cools off again.

When you are ammo testing for BR. What criteria do you use to decide which ammo performed best?

Also how do you decide if a barrel is a "dud" or not? At what point do you give up on a barrel?

 

[JAS-SH]

If there was ever a round that couldn't kill a barrel it's the 22LR. Carbon buildup could eventually affect accuracy, but that too is way down the road. Only issue would be buildup at the throat.

My take is: if your .22LR gun shoots best when clean, then clean it, often. If it makes no difference then don't clean it that often.

I shoot a .22 Mag as my trainer. Whole different animal - 2200 FPS with 30 gr. pills. All with bullets with real copper jackets. I can go 100 rounds or so before my patches start coming out green. By that time I also get quite a bit of carbon on the throat. So, I clean it after every outing or two at the most. The longer I wait the longer it takes to clean the damn thing. The leade/throat gets pretty fouled in two outings (100~150 rounds) so I pay close attention to that.

So far so good. Then again, a different animal.

Best,

JAS

 

[Tim7139]

Tim your last statement would make some wonder. It could be true then again it might not. Online anyone of us can say anything. Some people say a lot others others try to show what they have observed.
You obviously know something of rimfire as the comments you make it wouldnt be possible for you to pull out of your ass without knowing something about this gig.
Your last reply regarding #3 was good and informative. We could say close to the peak of the pie.
I have been doing some testing of my own regarding cleaning and the carbon ring. Results have been interesting. I have not recorded accuracy differences yet.... BUT I have a rifle that when colder then -8⁰c to -10⁰c there was 1 ammo that would lose stability and key hole. I cleaned the carbon ring and it seems that fixed the stability issues. Now I only had 1 cold day and it was barely cold enough to be absolutely sure that all stability issues are corrected. That topic will have to wait until next winter unless it cools off again.

When you are ammo testing for BR. What criteria do you use to decide which ammo performed best?

Also how do you decide if a barrel is a "dud" or not? At what point do you give up on a barrel?

OK this is tough(er).
I guess first re testing, IMO you learn zero until warmer weather, unfortunately.
I shoot no rimfire during winter, mostly because match ammo simply will not perform for a variety of reasons.
Cleaning ring, buy some C4 carbon cutter, let it soak 10-15 min.....done.Safely wipes out the ring. If you use anything abrasive you risk a less than round chamber.
The ammo testing is challenging mostly because realize it or not with a lot of the guns lots of you guys are shooting, there is precision robbing stuff going on, barrels, ignition, rest/handling, and on.
The one thing about testing for BR, first you have to establish all you are doing is ammo testing.
I compete, have had success and know I am shooting higher grade equipment/optics/ precision rests which reduces many variables, you don't have that investment. You have to have an established baseline......with my equipment, I have one.
Among the single biggest errors guys make testing ammo is not realizing when to do it. You need testing weather when it is calm and you’re not dealing with tons of other variables.
everything is consistancy.....you get unexplained flier, more than one, that’s not match ammo IF you can honestly say you did’nt screw up, miss a condition.
I shoot few groups, most guys do not. Get flags, learn to use them, I shoot over 4-6 and often I have an expensive bluetooh anemometer down range.
Under the right conditions, if I can shoot an IR card @250 15-18 X’s that ammo is in the running.
Even then If I use it, I will shoot a few of my close sanctioned matches before I use it in any State or Regional championship match. I’ve been shooting IR 50/50 primarily for 30 years so you also, kind, develop a feel for whats good, and really good...whats really needed to with a big match.
Also helps to network about lots available that are really working and that takes time.
The good news is quality match ammo has never been better overall, BUT, you are kidding yourself expecting match performance from CCI, mid level stuff.
ELEY black/red box, Lapua, CenterX, Midas..... not cheap but here, you get what you pay for.......that’s about it

 

[Gleedus]

The 50 yd vs 200 yard is a interesting noncompatible comparison. Push that to 400 yards and....

My 400 yard testing plate (actually 411 yd) has 3 groups on it currently 6-8" wide and 24" tall. Heres a picture of one.

the same ammo at 211 yds is 4.5"-5" at 50 yards at that time it was shooting that ammo in the 0.7s
Now the best shooting 50 yard ammo was Center X and Eley match. But neither of those 2 did well at long range. Almost double the group size.
The reason that 50 yard BR accuracy doesnt matter for long range is any improvement in 50 yard accuracy is soon masked by the awful affects of ammo quality and become negligible.
Now I am in no way suggesting that a rifle that shoots 2" 50 yard groups will do well at 200!

Now we could open the topic of tuning and positive compensation... it could be that a BR rig properly tuned would be a improvement. If I remember correctly a guy shot a box at 200 with Eley Match with a BR rifle and had a lovely group. Was that a one off or repeatable? I would like to think it would be repeatable.

 

[justin amateur]

It's repeatable, but it won't be accomplished with an off the shelf rig.

Y'er gonna need some serious wind reading skill,
flags, setup, purpose built rifle and lot tested cartridges.

200 yards with rimfire

Finally had a no wind morning so I gave the Lapua Biathlon Xtreme a try. 50 shots at 200 yards with a CZ 455 Varmint, Lilja barrel, Sinclair bipod and bag This box was extremely erratic as the results and chrony numbers show. The Lapua X-Act did a bit better Brand/label/price is no...

www.snipershide.com

Think about that... 200 yards and a 3 inch 50 shot group.
At 100 yards it'd work out to a 1 inch 50 shot group
and at 50 yards expect 1/3rd inch spread center to center.
At 50, you could hide that 50 shot group under a dime, with room to spare.

 

[AGrizz]

Well, still waiting for your answer about personal experience measuring match barrel blanks.
Guess I wait a while because it seems that would be ZERO.
Ever seen one?
Ever seen one fit?
Been inside or within 10 miles of a barrel shop?
Yeah, I though so.
Dif between me and you......I have the creds to back it up.
you never took me up on the phone #, I’m guessing because you don’t have a clue who the guy is do you?

Nice site by the way. You do realize the topic is RIFLE BORES don’t you Forrest?
Turn around.........look at the pretty bear.

I certainly have to give you credit for your persistence. Stubborn and lazy as you are egotistical at least you are not upset here. Absolutely nothing is settled science. The real answers are with people like justin and his ability to ask, "What if, what is and why"?

If you wish to side track the conversation about a measurement device then you can go there yourself.

Have you ever been in a tool and die shop?
Have you ever worked on a CNC machine tool that makes your wonderful barrels?
Have you ever been inside of an aviation tooling and machine pro business?
Have you ever worked in an metrology lab that inspects barrels you are so fond of talking about?

Nope didn't think so.\
You are a shooter that is all.
Turn around ......................................... look at the pretty bear.

 

[Tokay444]

I stayed in a holiday inn express last night.

 

[Tokay444]

Oh, I also cut a Boeing 737 Max landing gear this week, took it to the metrology lab, and verified its accuracy.

 

[Gleedus]

OK this is tough(er).
I guess first re testing, IMO you learn zero until warmer weather, unfortunately.
I shoot no rimfire during winter, mostly because match ammo simply will not perform for a variety of reasons.
Cleaning ring, buy some C4 carbon cutter, let it soak 10-15 min.....done.Safely wipes out the ring. If you use anything abrasive you risk a less than round chamber.
The ammo testing is challenging mostly because realize it or not with a lot of the guns lots of you guys are shooting, there is precision robbing stuff going on, barrels, ignition, rest/handling, and on.
The one thing about testing for BR, first you have to establish all you are doing is ammo testing.
I compete, have had success and know I am shooting higher grade equipment/optics/ precision rests which reduces many variables, you don't have that investment. You have to have an established baseline......with my equipment, I have one.
Among the single biggest errors guys make testing ammo is not realizing when to do it. You need testing weather when it is calm and you’re not dealing with tons of other variables.
everything is consistancy.....you get unexplained flier, more than one, that’s not match ammo IF you can honestly say you did’nt screw up, miss a condition.
I shoot few groups, most guys do not. Get flags, learn to use them, I shoot over 4-6 and often I have an expensive bluetooh anemometer down range.
Under the right conditions, if I can shoot an IR card @250 15-18 X’s that ammo is in the running.
Even then If I use it, I will shoot a few of my close sanctioned matches before I use it in any State or Regional championship match. I’ve been shooting IR 50/50 primarily for 30 years so you also, kind, develop a feel for whats good, and really good...whats really needed to with a big match.
Also helps to network about lots available that are really working and that takes time.
The good news is quality match ammo has never been better overall, BUT, you are kidding yourself expecting match performance from CCI, mid level stuff.
ELEY black/red box, Lapua, CenterX, Midas..... not cheap but here, you get what you pay for.......that’s about it

Cold vs warm That has been this winters project or one of them. I now have a good baseline from -10⁰ to 0⁰c/ 14⁰f to 32⁰f. I hope your right and it shoots better warm! In my books that would be a shooter!

I think you nailed it on the differences. When we start looking for the fine details of accuracy a bipod and rear bag can very easily hide results. That is one of the reasons I tell guys starting into the PRS rimfire to buy reasonable priced ammo and just shoot. They can't shoot the difference anyway.

I can attest to ignition... I changed triggers on my Rim X accuracy went to pot... bad even for a field shooter. went back to the old one problem solved.

Fliers... ya.... I really notice a difference at 50 yards. The more I pay the better it shoots normally. Center X, Eley match, Tenex are my three best. I have never tried midas or exact. But for what we do I cant shoot the difference so center X is good.

So your looking at your scores to determine ammo quality/ compatability? In other words statistics.
Group extreme size is not as important as SD.

In doing my long range testing it became apparent to me that using group size has significant problems as I had ammo that would have 1 flier and made a 7" group but the groups SD was better then other groups. I started looking at groups based in their SD now.

Thinking on group size A 250 on a IR 50/50 would have to be a sub 0.5" group right?

 

[IdealJoe]

Tim Tim Open Mouth and insert foot. This may get you started if you have the ambition. I am not here to try to impress you or anyone else here. This settled science and fact that all refer to is straight out horse shit.

Try to start here and I can keep you going if you wish. https://metrology.news/integrated-in-process-bore-gauging-for-cnc-machine-tools/

Not sure what your problem is AGrizz. You attacked Tim with things I stated so I assume you are attacking me too. Your link to cnc air gage blah blah blah means what exactly? Do you really think the inspection of a near perfectly round cylinder with an air gage compares to a rifle bore with rifling in it? It's been done... and doesn't work. But by all means, keep screaming as loud as you can. Run off the guys with actual knowledge on the topic.

I've recognized other members around here that absolutely know this stuff and have the credentials but stay silent. I think I know why. I'll be going away now too.

 

[Gleedus]

Not sure what your problem is AGrizz. You attacked Tim with things I stated so I assume you are attacking me too. Your link to cnc air gage blah blah blah means what exactly? Do you really think the inspection of a near perfectly round cylinder with an air gage compares to a rifle bore with rifling in it? It's been done... and doesn't work. But by all means, keep screaming as loud as you can. Run off the guys with actual knowledge on the topic.

I've recognized other members around here that absolutely know this stuff and have the credentials but stay silent. I think I know why. I'll be going away now too.

You have to remember many of us absolutely dont know this stuff and are learning. The reasearch I did looked like a air gauge would work. Up until now we only got told how stupid we are it wont work. Nobody said WHY it wont work.
Finally after a bunch of name calling someone (you) says it wont work because of the rifling. Bingo makes perfect sense the additional clearance would make the resolution very poor not to mention any rifling variations. The problem is that we are all told how stupid we are so are now sceptical of your side of the discussion and will have to research some more...
Stay calm dont get to yelling around and stay in the discussion we may learn something. Over here. I for one appreciate you chiming in.

 

[Tokay444]

There are air gauges that will work. Just not the ones linked.

 

[justin amateur]

I have decided against air guaging.
When I win the lottery, this is what I will use to measure barrel wear.
I use cadd (computer assisted design drafting)
laser scanning large areas to create 3D models to earn a living,
so lidar point fields I can work with.

Automated barrel inspection and 3D measurement - Novacam

www.novacam.com

 

[AGrizz]

I have decided against air guaging.
When I win the lottery, this is what I will use to measure barrel wear.
I use cadd (computer assisted design drafting)
laser scanning large areas to create 3D models to earn a living,
so lidar point fields I can work with.

Automated barrel inspection and 3D measurement - Novacam

www.novacam.com

There are numerous other systems that accomplish this as well. However not the particulate, flaws or finish evaluation. Those evaluations may be accomplished with different tests. Yes they are pricey. People just have to open their eyes and minds. They just do not wish to spend the time and effort it takes to learn.

 

[grauhanen]

So your looking at your scores to determine ammo quality/ compatability? In other words statistics.
Group extreme size is not as important as SD.

In doing my long range testing it became apparent to me that using group size has significant problems as I had ammo that would have 1 flier and made a 7" group but the groups SD was better then other groups. I started looking at groups based in their SD now.

Thinking on group size A 250 on a IR 50/50 would have to be a sub 0.5" group right?

Generally speaking, the smaller the group size a rifle/ammo shoots the better the score is likely to be. I seem to recall a reference point of consistent .276" (or better) five shot groups at 50 yards as the starting point to be competitive.

It's a good observation about the problem of using group size in long range testing. A single flier can really spoil an otherwise promising group. But the problem is more than that because the further the distance, the more difficult it is to shoot consistent groups, especially in outdoor conditions.

MV variation plays havoc with vertical spread. With SV ammo, each 10fps difference in MV between rounds results in 1" of vertical at 200 and about 2.3" at 300 yards. That adds up to potentially considerable vertical spread with a box of good ammo with a 30 fps ES.

In addition, even a slight wind, possibly undetected by the shooter across 200 or 300 yards, can exacerbate group size inconsistency. Each 1 mph of crosswind causes 1.3" of drift over 200 yards, about 2.8" at 300. With .22LR, it's very difficult to account for even subtle but impactful changes in wind across 200 to 300 yards and how they will affect POI.

The result is that even with perfect shot execution it's increasingly difficult to shoot consistent groups the further out the target. From that it follows that it's difficult to test .22LR ammo at long range. How can the shooter know what's responsible for the results? Is it vertical spread caused by ES? Is it the result of air movement? Is it imperfect shot execution? Is it something else?

Statistical data from chronographing ammo can help, but it offers no guarantees. There's no rule that says the ammo with the lowest SD (or ES) must produce the best results. Vertical and horizontal spread may be caused by factors other than gravity or air movement, and these are not necessarily predictable.

Group size more than doubles between 50 and 100, on average by the order of 2.8. Between 100 and 200 it will be by a greater ratio, and greater still between 200 and 400.

What should the shooter do? Select ammo that not only has a low SD but is proven to shoot consistently well at 50 and 100 yards. If it can't do well at those distances, it shouldn't be expected to perform well further out.