Ruger American Rimfire Long Range Target

[EHG]

Fascinating!
We're talking about a .22LR bullet designed to shoot short range with round or flat pointed head and flat base. The variables between lots become even more complex.
I've shot SK RM and Center-X in my 40XB and I have test groups that reveal sometimes huge differences between lots of ammo and different firearms. There's a reason why top end shooters have their firearms tested at Lapua or Eley and then buy a case or two of the most accurate.

PRS style shooting and looking to extend the range of the .22 LR accurately will be most challenging. Anytime long range shooting happens the bullet shape changes immediately to a spitzer/boat-tail combination and bullet staying supersonic to the target. Since, that is not happened to the .22LR yet, you are at the mercy of wind change of a small projectile that will open or tighten a group at any range. Are you guys using wind flags and watching them change all the way to 300 yds? I use flags to 50yds and have seen bullet deflection there.
Naturally, I'm also awaiting new developments that happen, not luck.

Whether we are talking about a Ruger or Vudoo rifle is immaterial. One is Production, the other is custom Open class.

 

[TheWhole9Yards]

Sorry to the original poster for your thread going to the same endless nonsense that all threads that don’t fit someone’s rimfire thoughts. I hope you are going to the next crps I’d like to take a peak at this gun

Yea no worries, not your fault.

I won’t be at the next CRPS unfortunately, but will maybe see you next year at NRS matches.

 

[enefgee]

Might be throwing gas on this dumpster fire of a thread but here it goes, groups described in my earlier post - where the avg group size data came from.

51Yards
View attachment 424315

106Yards
View attachment 424316

186Yards
View attachment 424317

Damn, that's good shooting. Didn't Jeff Cooper once say that someone who hasn't done a night landing on an aircraft carrier should not criticize someone who has? Nice landing.

 

[TheWhole9Yards]

Had some decent weather so I got out yesterday morning to do some more ammo testing @ 51 yards.



Its almost common knowledge that temperature impacts the performance of .22LR, so I decided to expand some ammunition in the name of "science" and see how much it does impact group sizes. I shot from the same shooting position, at the same time of day - one month apart. Yesterdays test was 5C and no wind, previous test was 12C with no wind as well.

This time I tested SK Match, Lapua Center-X, and also found a box of Eley Tenex in the depths of my collection. I shot ten groups of five rounds for every variety, then measured and averaged the results.

51yard Avg @ 5C
SK Match: .717"
Lapua Center-X: .585"
Eley Tenex: .584"


51 Yard Avg @ 12C
SK Match: .450”
SK Long Range: .486”
Lapua Center-X: .440”

**Disclaimer**
Before the thread police arrive I should mention 3 things:
1. The previous test was 3 groups of 5 shots each
2. The SK and Lapua in both tests came from the same lot #
3. I find shooting groups like this painfully boring, and cannot see how benchrest shooters find enjoyment in this type of activity

 

[Mystic Precision]

Thanks for continuing to post your results. How did the SK rifle match groups look in the cold? did the groups have more vertical?

I am glad you noticed that cooler temp increased the SK and Lapua grouping in a negative manner. Exactly what I have noticed and it gets much worst once you go past 100yds.

Jerry

 

[TheWhole9Yards]

Thanks for continuing to post your results. How did the SK rifle match groups look in the cold? did the groups have more vertical?

I am glad you noticed that cooler temp increased the SK and Lapua grouping in a negative manner. Exactly what I have noticed and it gets much worst once you go past 100yds.

Jerry

Yes minor vertical stringing in some groups, as the sun came out and the temp started to rise it was less noticeable and groups started to tighten up. Also what was noticeable was the affect of the ammo cooling, I hung my targets and setup before taking my ammunition out of my range bag. I used the same mag for each group so I did a reload between each group, I could be crazy but I felt I got more flyers the further into the set I got, ie as the ammo cooled it was less consistent than when it was still room temp inside my bag. I kept all the ammo in my range bag until I was ready to shoot the next brand.

 

[old303]

Keep ammo inside your coat until you're ready to load?

 

[Mystic Precision]

Yes minor vertical stringing in some groups, as the sun came out and the temp started to rise it was less noticeable and groups started to tighten up. Also what was noticeable was the affect of the ammo cooling, I hung my targets and setup before taking my ammunition out of my range bag. I used the same mag for each group so I did a reload between each group, I could be crazy but I felt I got more flyers the further into the set I got, ie as the ammo cooled it was less consistent than when it was still room temp inside my bag. I kept all the ammo in my range bag until I was ready to shoot the next brand.

Not nuts at all. I did the reverse test in the summer knowing that I was going to compete in the cold/fall. I varied the temps and saw my results change dramatically as it cooled. It lead me to run biathlon ammo at the match.

For winter, I would put some hot bottles into the cooler and heat up the ammo (around 25 to 30C buys you time). Remove and shoot as soon as possible. if it took a while, I would just toss the mag back into the "heater" and let the temp ramp up. What you saw around 12C as being a nice min temp is what I also see. If I can keep the ammo well above this, I have time to shoot without much fuss.

I know when my ammo is too cold cause I will start to drop shots out the bottom... ie vertical stringing. Then it is back into the heater

Worked like a charm... can't do it in a match easily but no worries for a nice day at the range.

Jerry

 

[Longstud]

Buy lots of magazines and load all your ammo into them in the warmth of your house. Keep them warm with chemical heaters and storing in interior pockets of ur insulated cold weather gear. Even just body heat will keep them warm enough if your prepared and shoot the stage in a timely manner. It does work and most match ammo starts too loose its edge once the colder temps arrive and Ive seen the same results once lower than 12C. Shoot a magazine of warm ammo 20to25C and then shoot a magazine of the same ammo from the same box(Lot) thats sat outside and cooled to the ambient colder air temp of low single digits or colder. Youll quickly see the results especially 100yds or farther! Temp is huge in rimfire ammo. Great info TheWhole9Yards and Jerry(Mystic). Im sure many were not aware of this fact but a simple test will prove it real quick.

 

[Mystic Precision]

There is so much debate over things that real world testing would resolve

Keep good notes, be aware of conditions, make good pulls....

Jerry

 

[RabidM4U5]

Its almost common knowledge that temperature impacts the performance of .22LR, so I decided to expand some ammunition in the name of "science" and see how much it does impact group sizes. I shot from the same shooting position, at the same time of day - one month apart. Yesterdays test was 5C and no wind, previous test was 12C with no wind as well.

Yep, temperature certainly affects the characteristics of .22LR ammo. In a negative way? Your results might suggest so.

What physical effects does temperature have? It slows down chemical reactions. Primer ignition is less vigorous, powder burn is slower. Pressure curve is altered. Barrel steel contracts, tightening bore diameter. Friction coefficient of lube is altered. Bullet lead becomes less malleable (super cold metal can shatter, hot metal will bend or even melt). Did I miss anything? Probably, but you get the point.

Does that make ammo shoot poorly in a directly proportional relationship to temperature? That is undetermined.

Certainly, for the stated above changes to chemical reaction and physical properties, a certain lot of ammo will behave like a different load in relation to temperature changes. Centerfire handloaders know this well and develop specific loads for warm and cold conditions. Temperature directly effects muzzle velocity (and as a result, barrel time of the bullet). Changes in the pressure curve affect barrel vibration. These two factors alone alter the vibration conditions at the muzzle at the time of bullet exit. When everything lined up well at one temperature, it may not do so at a different temperature. Perhaps there are cases of ammo that did not shoot well during the warm conditions that shot well in the cold?

What I can put out there is that I shot the 1/4' challenge in cold weather, and I used a tuner on my rifle. I did not keep my ammo warm (RWS R-50), but let it acclimate to ambient temperature on the bench (consistency is key). The tuner serves to neutralize the effects of load property changes in relation to muzzle vibration at the time of bullet exit. Does cold temperature make the ammo less accurate? As I stated earlier, undetermined. Maybe I would have shot some groups in the 0.1's if it was warmer, I don't know.

This is only meant to help facilitate understanding of rimfire behavior and promote healthy discussion, not to be a "thread police".

If you were to add a pressure pad to the forestock, or add a muzzle brake if your barrel is threaded, you will most likely see a change in your group averages in the cold weather (also likely to change results in the warm). For the better or worse? I can't say, it's just something to try.

 

[TheWhole9Yards]

Yep, temperature certainly affects the characteristics of .22LR ammo. In a negative way? Your results might suggest so.

What physical effects does temperature have? It slows down chemical reactions. Primer ignition is less vigorous, powder burn is slower. Pressure curve is altered. Barrel steel contracts, tightening bore diameter. Friction coefficient of lube is altered. Bullet lead becomes less malleable (super cold metal can shatter, hot metal will bend or even melt). Did I miss anything? Probably, but you get the point.

Does that make ammo shoot poorly in a directly proportional relationship to temperature? That is undetermined.

Certainly, for the stated above changes to chemical reaction and physical properties, a certain lot of ammo will behave like a different load in relation to temperature changes. Centerfire handloaders know this well and develop specific loads for warm and cold conditions. Temperature directly effects muzzle velocity (and as a result, barrel time of the bullet). Changes in the pressure curve affect barrel vibration. These two factors alone alter the vibration conditions at the muzzle at the time of bullet exit. When everything lined up well at one temperature, it may not do so at a different temperature. Perhaps there are cases of ammo that did not shoot well during the warm conditions that shot well in the cold?

What I can put out there is that I shot the 1/4' challenge in cold weather, and I used a tuner on my rifle. I did not keep my ammo warm (RWS R-50), but let it acclimate to ambient temperature on the bench (consistency is key). The tuner serves to neutralize the effects of load property changes in relation to muzzle vibration at the time of bullet exit. Does cold temperature make the ammo less accurate? As I stated earlier, undetermined. Maybe I would have shot some groups in the 0.1's if it was warmer, I don't know.

This is only meant to help facilitate understanding of rimfire behavior and promote healthy discussion, not to be a "thread police".

If you were to add a pressure pad to the forestock, or add a muzzle brake if your barrel is threaded, you will most likely see a change in your group averages in the cold weather (also likely to change results in the warm). For the better or worse? I can't say, it's just something to try.

Well said! There are many factors at play, rimfire is quite the can of worms.

You bring a up a good point about acclimating the ammo. What I did potentially had me send 5 groups at varying temps, should have either let it cool down fully or as mentioned by Old303, Jerry and Longstud I could have kept it warm. It would be interesting to see warm vs cold in those scenarios.

Which tuner do you run? I’m curious about them, but have not read up on them.

Perhaps I will experiment with muzzle brakes over the winter. I have a linear comp on my ORPS rig, can’t tell you if it makes a difference or not - I only put it on because it was cheaper than getting a thread cap.

 

[Longstud]

What kind of ammo do Olympic biathlon shooters use? What kind of barrels are on their rifles,are they the same variants as other models not designed for cold weather use,are the chambers,bore diameters ,lead angle the same? In warmer weather with you shooting with the same skill level and tuner tuned to that lot for the 20C weather youd have been producing and the first 1/8" or less club. The home brewer knows who Im speaking too.You adapt and make the best out of whats put in front of you but warmer weather will consistently produce smaller aggregate groups for 99.99% of the shooting populace. Ur the 00.01% HAHA still wanna sample ur brew Cheers

 

[RabidM4U5]

Which tuner do you run? I’m curious about them, but have not read up on them.

Perhaps I will experiment with muzzle brakes over the winter. I have a linear comp on my ORPS rig, can’t tell you if it makes a difference or not - I only put it on because it was cheaper than getting a thread cap.

I use Harrells. My opinion is that they're one of the better designs out there on the market. Yeah, by all means experiment with the muzzle brake. The whole operating principal of the tuner is that it puts weight forward of the muzzle, so does a muzzle brake. Difference being muzzle brakes tend to be several ounces lighter than a tuner, so for one it's likely not enough weight to get the full benefit, and neither is it adjustable. It's a shot in the dark if it'll improve things, though I would expect to see some observable change. Maybe you don't see a change in group average, but POI shifts with brake on, brake off. Tuners are commonly thought of as improving accuracy, but I can set it up in such a way that ruins accuracy, much worse than no tuner at all! My observation over the last few years messing with tuners is that once they are set up right for the barrel, it doesn't really matter what ammo you use so much as that ammo is a good lot. Eley, RWS, Lapua, Biathlon varieties, I've had good results with them all in various temperatures hot and cold.

What kind of ammo do Olympic biathlon shooters use? What kind of barrels are on their rifles,are they the same variants as other models not designed for cold weather use,are the chambers,bore diameters ,lead angle the same? In warmer weather with you shooting with the same skill level and tuner tuned to that lot for the 20C weather youd have been producing and the first 1/8" or less club. The home brewer knows who Im speaking too.You adapt and make the best out of whats put in front of you but warmer weather will consistently produce smaller aggregate groups for 99.99% of the shooting populace. Ur the 00.01% HAHA still wanna sample ur brew Cheers

It took me 2 years to pull off 1/4", shot the same lots of ammo in all weather conditions. 1/8"? I doubt it. Not with any of my current rifles and certainly not without sending a rifle off to a legit lot testing center with significant inventory, unless I won the random ammo lot lottery. The biathlon ammo in the cold, just going off my memory from chrono testing, shot with comparable MV to standard velocity ammo shot in warm weather. Cold drops MV around 40 fps if I recall correctly (obviously, more extreme cold, more loss of MV). As Jerry noted, you'll see the vertical spread get worse over distance. This makes sense, slower rounds drop more than faster rounds. A velocity spread of 950fps to 1000 fps will have greater vertical spread on target than a velocity spread of 1050fps to 1100 fps, even though the extreme spread is 50fps for both groups. Very obvious at longer ranges. For you long range guys, it makes sense to switch over to biathlon ammo when shooting in the cold, since it'll behave more like the standard velocity stuff you use in the summer.

 

[Alchemist]

Isn’t the air being more dense at cooler temperatures a big factor too?

I’m not a ballistics expert but I am a chemist. I don’t think the temperature difference between 5C and 24C is going to have a huge difference on the rate of the combustion reaction n the cartridge but temperature will have a larger effect on the volume of the gas evolved from the reaction (and therefore the velocity of the projectile expelled by the pressure in the barrel). PV=nRT rearrange for V etc.

Have you tried warming the barrel to keep it a constant temperature to see if that makes any difference?

I find this topic pretty interesting so please excuse me if this is just newbie rambling.

 

[grauhanen]

Isn’t the air being more dense at cooler temperatures a big factor too?

Air density is a combination of air pressure, temperature, and humidity. Cooler air is more dense than warmer air. Dry air is denser than wet air. Both will cause more drag on bullets. But the atmospheric conditions don't have a significant impact on .22LR ballistics. Ballistics calculators support this.

When temperatures range between -10 and about 15 degrees Celsius and humidity ranges between 20 and 95% are factored in, the difference in results downrange are not more than about five inches of vertical dispersion out to 300 yards. More significant is the muzzle velocity difference between one round and the next. Each 10 fps difference in MV between one round and another results in about .25" of vertical at 100 yards, over 2" at 300.

Of course, ballistics calculators can't account for the very real issues discussed by Rabid in his post above. Cooler temperatures can affect the chemical reactions involved with .22LR as well as the barrel itself. These may well cause even more vertical dispersion than the five inches that the ballistics calculators show on paper.

More difficult to know is how colder temperatures will affect a schooter. They probably don't cause improved results compared to when temperatures are more comfortable. Rabid's successful 1/4" challenge is a testamentt to his ability to shoot well in less than ideal conditions.

 

[Mystic Precision]

Isn’t the air being more dense at cooler temperatures a big factor too?

I’m not a ballistics expert but I am a chemist. I don’t think the temperature difference between 5C and 24C is going to have a huge difference on the rate of the combustion reaction n the cartridge but temperature will have a larger effect on the volume of the gas evolved from the reaction (and therefore the velocity of the projectile expelled by the pressure in the barrel). PV=nRT rearrange for V etc.

Have you tried warming the barrel to keep it a constant temperature to see if that makes any difference?

I find this topic pretty interesting so please excuse me if this is just newbie rambling.

Many gunpowders are temp sensitive. This changed when VARGET came out many years back. Since then, for centerfire type powders, there are formulations that are very temp stable... ie little changes in kaboom over a wide range of temps. That is not the case in powders used in rimfires and for the most part, handguns.

It is very easy to test as was shown in this post. Whatever temp you are now, heat or cool the rimfire ammo and you will see a change on target

wrt to barrel temp being cold, I see it having less affect ... surprisingly. In my tests, whether hot or cold, I am not touching the barrel... just the ammo. for cold, I am still around or above 0C.. maybe if you drop well below that, the steel can change???? not interested in testing in that type of cold

when using temp unstable powders, I would vary my powder charge every 10 to 15C to keep things in tune... kind of a pain but no biggie for practise or varminting ammo.

For competition, I run temp stable powders and one less thing to worry about.

Air density really doesn't change your POI a whole lot. I run JBM and there is a altitude drop card feature. It lets you set the DA change. I use 1000ft and 4000ft. You can see the change from 0ft to 4000ft, and even at 1000yds, the amount for many CF combos isn't all that great

I would be really surprised if any one location would have a 4000ft DA change during a day w/o a major storm system coming through.

Even from sunny to pouring down rain... the drop really doesn't change much

Jerry

 

[Longstud]

Many gunpowders are temp sensitive. This changed when VARGET came out many years back. Since then, for centerfire type powders, there are formulations that are very temp stable... ie little changes in kaboom over a wide range of temps. That is not the case in powders used in rimfires and for the most part, handguns.

It is very easy to test as was shown in this post. Whatever temp you are now, heat or cool the rimfire ammo and you will see a change on target

wrt to barrel temp being cold, I see it having less affect ... surprisingly. In my tests, whether hot or cold, I am not touching the barrel... just the ammo. for cold, I am still around or above 0C.. maybe if you drop well below that, the steel can change???? not interested in testing in that type of cold

when using temp unstable powders, I would vary my powder charge every 10 to 15C to keep things in tune... kind of a pain but no biggie for practise or varminting ammo.

For competition, I run temp stable powders and one less thing to worry about.

Air density really doesn't change your POI a whole lot. I run JBM and there is a altitude drop card feature. It lets you set the DA change. I use 1000ft and 4000ft. You can see the change from 0ft to 4000ft, and even at 1000yds, the amount for many CF combos isn't all that great

I would be really surprised if any one location would have a 4000ft DA change during a day w/o a major storm system coming through.

Even from sunny to pouring down rain... the drop really doesn't change much

Jerry

Agreat many that read our posts may not understand some of the terminology. So probably a good idea too give definitions to some of our abbreviations. We sometimes forget our world is different to others and what is everyday to us is foreign to many ie DA which many seasoned shooters and pilots will recognize as Density Altitude. Most wont have the foggiest and its our job to provide them with the tools to improve and learn. The great thing about this forum is the knowledge that can be gleaned from all the experience and knowledge many of our members have. I have learned many things from members being candid and posting freely their knowledge. Too thank just a few off the cuff 45 Auto, RabidM4U5,Grauhanen,Maple57,EagleEye,Mystic,Jefferson, and a lot of others that Ive forgotten cuz Ive sucked back a few grain beverages and im gettin old. Haha burn powder, shoot safe,have fun and pass this great sport on too anyone thats interested. Leave ur knowledge and guns too someone wholl follow your well placed footsteps!!

 

[TheWhole9Yards]

More difficult to know is how colder temperatures will affect a schooter. They probably don't cause improved results compared to when temperatures are more comfortable. Rabid's successful 1/4" challenge is a testamentt to his ability to shoot well in less than ideal conditions.

Agreed, cold hands and fingers don't help the situation.

 

[zombieprepping]

Came here for a rifle, left with SCIENCE