Velocity equals accuracy? Ruger Precision Rimfire

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Matapatapa

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Hey everyone.

I picked up a RPR in 22lr a few months ago, and just crossed the 1000 round mark.

This is the first rifle I've spent significant time with, so this could all be the thing behind the rifle being the problem.

Typically from what I read and hear, the faster and transonic velocity ammunition is supposed to be less accurate...

So far I've tried

Eley club, sport
CCI clean, cci velocitors, cci standard LRN, cci mini mags, cci quiet and subsonic HP
Federal gold medal match, and the HV version of it and Federal RTP


I'm far from a good shooter, probably below average honestly. Yet for some reason the slower ammo I pick, the worse my groups are... unless I'm using some bulk ammo like herters or winchester m.22 in which case eley sport outperforms it by a wide margin.

At 50m, from all the time I've spent, excluding bulk ammo and super budget like American eagle and Winchester wildcat

HV ammo -> 0.4-1.2 inch groups with 5 rounds depending on the ammo, I seem to do best with cci mini mags here
Standard -> 1.3-1/5 inches best with Eley club
Any subsonic -> 2-4 inches

Given that the wide majority of people provide the opposite data, I'm wondering what CGN's thoughts on this are.

My personal theory is the faster the ammo the less time it spends in the barrel; so my personal flinching or wobbling has a reduced effect.

I'm shooting off a Caldwell handy NXT in the front, and traditional shooting bags for front and rear on the backside, the rear bag is resting on the front one lying down on its side for elevation reasons.

Maybe just switch to a better rest?
 
I think a smaller faster bullet shoots straighter, and has less bullet drop. Also less time in air to be affected by wind too. Match ammo is for sure the way to go for consistency . The rest is up to you.
 
The subsonic velocity ammo is considered to be better because it doesn’t suffer from a loss of stability during the transonic range between super and subsonic. In your situation, this could mean that you are getting better groups with the supersonic velocity ammo initially because you are shooting groups at distances close enough where you don’t see that transonic phase. Therefore like you suggested the bullet could be less prone to post-shot shooter influence, although the difference could be marginal. If you were to stretch out your testing to 100yds and beyond you may notice that the subsonic ammo will hold better groups.
 
Velocity isn't everything . . . It's the only thing!

When velocity is very consistent, 1" at 100 is possible even with high velocity American Made.

Very consistent and American made is an oxymoron.

Although I only fired five shots with TENEX, the velocity was from 1076-1086 and the group measured 0.45"

When CCI MiniMags were within 10 fps the accuracy was in the 1" class. The next ten shots varied about 75 fps and groups then go All 2 Hell. Don't ever get your hopes too high.
 
Good quality standard velocity (SV) ammo can often be expected to have better consistency of muzzle velocity (MV) than most high velocity (HV) ammo. There's many differnt varieties of SV ammo and not all of it is near equal. Match ammo is standard velocity, it is more expensive, and it is more accurate. HV ammo is typically less expensive and less accurate.

But velocity isn't everything for several reasons, the main ones briefly summarized below.

Differences in MV do not always translate to significant increases in group sizes at 50 yards. While it's important to have relatively consistent MV's to achieve very good accuracy, especially as distance increases, at 50 yards a difference of 50 fps between one SV round and the next amounts to about .28" in vertical. A difference of 100 fps between rounds results in .66" of vertical. The size of the groups described by the OP -- well over one inch -- are too large to be explained by an excessive extreme spread (ES) alone.

It's important to understand that it isn't only the MV of the ammo that contributes to its accuracy. Consistency in all the components that go into each round and the consistency of the manufacturing process also play a critical role in ammo accuracy. The priming, the amount of propellant, the weight of the bullet as well as its diameter all must be consistent. Not only that the application of the primer in the case, the seating depth of the bullet, the crimping of the case -- all part of the manufacturing process -- together with the machinery that does the job must also be as consistent as possible as they too play a role in the accuracy of the ammo.

There is also the role of the rifle itself. I don't know anything about the OP's rifle, a RPR or Ruger Precision Rimfire, so I'm not suggesting anything about it. But it's important to keep in mind that some rifles are simply better shooters than others and no matter what ammo is used they will be hard-pressed to be accurate.

The shooting platform may also be a factor worth taking into consideration. Is the rifle shot off a solid bench or table? If there is any movement in the bench or table that will affect accuracy. The rest must also be taken into account. If the rest is the Caldwell Handy Shooting Rest NXT shown below, its lightweight construction may not necessarily be helping the cause.

 
Standard velocity has less wind drift than high velocity because it has less drag. Match ammo is standard velocity . I never shoot high velocity but I know that cheaper standard velocity ammo can be pretty good at 50 yards and at 100 you can't trust it most look good then one will drop down a few inches and one side or the other
 
lucas.c said:
The subsonic velocity ammo is considered to be better because it doesn’t suffer from a loss of stability during the transonic range between super and subsonic. In your situation, this could mean that you are getting better groups with the supersonic velocity ammo initially because you are shooting groups at distances close enough where you don’t see that transonic phase. Therefore like you suggested the bullet could be less prone to post-shot shooter influence, although the difference could be marginal. If you were to stretch out your testing to 100yds and beyond you may notice that the subsonic ammo will hold better groups.
Click to expand...

I did not think of that, I'll stretch out and see what's what next time I do a range trip.

grauhanen said:
Good quality standard velocity (SV) ammo can often be expected to have better consistency of muzzle velocity (MV) than most high velocity (HV) ammo. There's many differnt varieties of SV ammo and not all of it is near equal. Match ammo is standard velocity, it is more expensive, and it is more accurate. HV ammo is typically less expensive and less accurate.

But velocity isn't everything for several reasons, the main ones briefly summarized below.

Differences in MV do not always translate to significant increases in group sizes at 50 yards. While it's important to have relatively consistent MV's to achieve very good accuracy, especially as distance increases, at 50 yards a difference of 50 fps between one SV round and the next amounts to about .28" in vertical. A difference of 100 fps between rounds results in .66" of vertical. The size of the groups described by the OP -- well over one inch -- are too large to be explained by an excessive extreme spread (ES) alone.

It's important to understand that it isn't only the MV of the ammo that contributes to its accuracy. Consistency in all the components that go into each round and the consistency of the manufacturing process also play a critical role in ammo accuracy. The priming, the amount of propellant, the weight of the bullet as well as its diameter all must be consistent. Not only that the application of the primer in the case, the seating depth of the bullet, the crimping of the case -- all part of the manufacturing process -- together with the machinery that does the job must also be as consistent as possible as they too play a role in the accuracy of the ammo.

There is also the role of the rifle itself. I don't know anything about the OP's rifle, a RPR or Ruger Precision Rimfire, so I'm not suggesting anything about it. But it's important to keep in mind that some rifles are simply better shooters than others and no matter what ammo is used they will be hard-pressed to be accurate.

The shooting platform may also be a factor worth taking into consideration. Is the rifle shot off a solid bench or table? If there is any movement in the bench or table that will affect accuracy. The rest must also be taken into account. If the rest is the Caldwell Handy Shooting Rest NXT shown below, its lightweight construction may not necessarily be helping the cause.

Click to expand...


That is the rest, it does wobble a bit..but not too much really. I'm shooting off of a bench, pretty stable but the stand/bags setup I have currently is still in the 50/50 area, where it's pretty decently stable but at the same time the rifle does move with my movement and does go off target after a shot; It's not like one of those vice-grip style solutions. My own movement changes the crosshair point of aim by about 0.3-0.5 inch with my normal breathing cycle.


Further details about the rifle if I may add; It's the standard RPR with the 30moa factory rail on top; on top, I've got a Bushnell banner 6-24x dusk and dawn optic. Very high magnification for a 22lr, but I only really just punch paper so high mag works just fine for me for shooting and spotting after the fact.
 
Matapatapa said:
That is the rest, it does wobble a bit..but not too much really. I'm shooting off of a bench, pretty stable but the stand/bags setup I have currently is still in the 50/50 area, where it's pretty decently stable but at the same time the rifle does move with my movement and does go off target after a shot; It's not like one of those vice-grip style solutions. My own movement changes the crosshair point of aim by about 0.3-0.5 inch with my normal breathing cycle.
Click to expand...

If a rest wobbles even a wee bit, that usually translates to quite a lot of movement at 50 yards. One one-hundreth of an inch movement between the rest and the end of the muzzle of a 24" barrel results in about .75" at 50 yards, if my math is right (I'm not a math guy) . There are shooters' breathing techniques that can help with the effects of natural breathing on target results. Follow through technique is important too. You don't want to be looking at where your bullet hits the target too soon.
 
grauhanen said:
If a rest wobbles even a wee bit, that usually translates to quite a lot of movement at 50 yards. One one-hundreth of an inch movement between the rest and the end of the muzzle of a 24" barrel results in about .75" at 50 yards, if my math is right (I'm not a math guy) . There are shooters' breathing techniques that can help with the effects of natural breathing on target results. Follow through technique is important too. You don't want to be looking at where your bullet hits the target too soon.
Click to expand...

Huh; really?

In keeping up with that I picked up a Caldwell rock JR; definitely much more stable than the last one.

I'll report back in a few days as to the results.
 
Velocity is certainly not everything with precision shooting, you're after consistency. Velocity is good for smacking whatever you hit hard, and doing it accurately at a long range requires some velocity. I would find what ammunition shoots consistently at 50yds and then walk it out.
 
Sort of. Hyper velocity might be consistent at 50 yards, but as it drops below the speed of sound it becomes unstable. A lot of shooters use ammo that stays below the speed of sound to avoid this, but if youre staying at 50 yards you shouldn't need to worry about this.

Another problem you may be having, is that the [adjustable objective] marks on your scope (if you have the adjustable objective.. Im not familiar with your scope) may not be correct. It might read as 50 but actually be 60. This means any slight movement of your head moves your cross hairs. This can move your groups quite a bit. An easy way to check this is to get set up on target and then move your head behind the scope, if your cross hairs move at all you need to adjust your objective until it doesn't move.
 
Matapatapa said:
Huh; really?
Click to expand...

Which part don't you understand? That a rest with wobble or movement in it can affect results significantly down range? That I'm not a math guy? That there are breathing techniques helpful to shooters? That follow through technique can be relevant to results on the target?

Seriously, I'm not a math guy. I was never enthusiastic about math classes.
 
If you can see movement of the crosshair on the target, that movement is amplified considerably when the bullet arrives at the target.
Think of it this way, the bullet will continue to follow the direction the muzzle was moving all the way to the target. By the time it gets there, it will have moved further than the crosshairs would indicate.
This is why a steady hold and controlled trigger squeeze is so important.
Follow through is particularly important with a .22, since the lower speed means the bullet remains in the barrel longer. Any movement on your part while it's still in the barrel translates to a wild shot.
The difference between "high" velocity and "standard" velocity isn't enough to significantly affect this, definitely not enough to make using high velocity ammo with it's transition through the speed of sound worthwhile.
I'd suggest simply shooting from a set of sandbags if that's convenient. No mechanical rest will ever be as stable as a bag of sand. They're not easily adjustable, however.
The less friction you have between whatever you use for a rest (both front and rear) the better, the rifle should slide freely without sticking or catching on the bag material.
An RPR is problematic in that respect, with its adjustable rear stock design and barrel shroud.
As friend of mine has one that's an absolute nail-driver, it's set up with a front bipod and a rear stock modification to allow it to ride the bag smoothly. He also removed the barrel thread protector, to eliminate carbon buildup in that area.
I was skeptical at first, but that rifle is outstanding when it comes to accuracy.
 
I suspect the Op is getting good accuracy at 50 yards with high velocity ammo because the bullet velocity has not degraded to the speed of sound yet at such close range.

Testing those same bullets at longer distances will surely produce very different results... Likely completely opposite.

Myself, I prefer bullets that shoot best at around 150-200 yards for all around use.

If the goal is to find ammo that shoots best at 50 yards, then just go with what works best at 50 yards and forget about the supersonic debate.
 
With my RPR 22LR, I made 0.55 MOA groups at 100m. Standard 1070 Velocity CCI.

As mentioned, keep away from transonic.

That's pretty standard advice for any caliber.

I'm thinking, heavier bullets doing 1050 would be interesting.
 
Humblepie said:
With my RPR 22LR, I made 0.55 MOA groups at 100m. Standard 1070 Velocity CCI.

As mentioned, keep away from transonic.

That's pretty standard advice for any caliber.

I'm thinking, heavier bullets doing 1050 would be interesting.
Click to expand...

That's incredible for a Ruger rimfire (and for CCI SV ammo). With that equipment, those .55 MOA groups (.55") at 100, deserve wide praise. Please post pictures of those groups and the rifle so that readers may laud the shooter because it's quite extraordinary.
 
Humblepie said:
With my RPR 22LR, I made 0.55 MOA groups at 100m. Standard 1070 Velocity CCI.

As mentioned, keep away from transonic.

That's pretty standard advice for any caliber.

I'm thinking, heavier bullets doing 1050 would be interesting.
Click to expand...

How many shots per group? That's quite remarkable.
 
grauhanen said:
Which part don't you understand? That a rest with wobble or movement in it can affect results significantly down range? That I'm not a math guy? That there are breathing techniques helpful to shooters? That follow through technique can be relevant to results on the target?

Seriously, I'm not a math guy. I was never enthusiastic about math classes.
Click to expand...

Sorry if that came off weird; that was not a "I don't understand" that was a "Oh really I never knew".

Text communicaiton really strips away context and body langauge unfortuantely.
 
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