Rim thickness gauge.

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fugemall

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I have started measuring rim thickness on my 22LR ammo. I was using a shot 22 250 case, then placing the LR round in it and measuring with calipers. This worked but was a little combursome. I see Hornady has a kit for measuring rim fire cases. I am cheap so I was looking at what I already have and try to make something work.

I have a hornady case comparator for centerfire. 22Lr fits into the 3-24 nicely, it is a little short though. I put an o ring (08 in the o ring kit) next to the shoulder tightened the set screw and have about .030" clearance.

This works for me and thought it would be worth passing on.
 

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That's a very good setup. Are you measuring to be able to adjust headspace? Not many people still measure rims for accuracy standards.
Here's some data in Post #2, it may save you some time. And there are other sources that dis-affirm rim measurement as a useful 'thing'. http s://www.rimfirecentral.com/threads/headspace-for-lapua-and-eley-and-sk-ammo.1334621/
 
Longstud said:
In my opinion if your buying quality ammo, measuring rims is a total waste of time!
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Your probably right. I am trying to take any variance of inconsistencies out of my ammo. I have found cci standard velocity shoots well but have flyers. If I can get it to shoot like SK or Eley match at well under half the price that's a win in my opinion.

I haven't had an opportunity to see if this will work or is a waste of time.
 
Buck1950 said:
That's a very good setup. Are you measuring to be able to adjust headspace? Not many people still measure rims for accuracy standards.
Here's some data in Post #2, it may save you some time. And there are other sources that dis-affirm rim measurement as a useful 'thing'. http s://www.rimfirecentral.com/threads/headspace-for-lapua-and-eley-and-sk-ammo.1334621/
Click to expand...
I will look into this when I get a chance.

Thanks
 
I spend a lot of time on RimfireAccuracy .com, SnipersHide .com(rimfire forum) and AccurateShooter .com. The general concensus is that rims are Not a critical factor in accuracy. Fractional variances in powder, bullet weight, bullet 'heel'
irregularities - all have more effect on shots. If you want to measure rims, you should use that info for headspace adjustments - simplest by using bolt shims. You'll still have to change that for some ammo, but you can start there.
IMO, you should spend some of that 'measuring time' reading what many have done and determined.
 
Buck1950 said:
I spend a lot of time on RimfireAccuracy .com, SnipersHide .com(rimfire forum) and AccurateShooter .com. The general concensus is that rims are Not a critical factor in accuracy. Fractional variances in powder, bullet weight, bullet 'heel'
irregularities - all have more effect on shots. If you want to measure rims, you should use that info for headspace adjustments - simplest by using bolt shims. You'll still have to change that for some ammo, but you can start there.
IMO, you should spend some of that 'measuring time' reading what many have done and determined.
Click to expand...
My goal is to take cci standard and get the best results possible. I could go and buy tenex at 32 dollars a box, or shoot 5 times as many cci and get better results then what I am currently getting (still waiting to prove this). The small sample of 600 rounds varied from .0390 to .0455". I separate the rounds in lots of +/- .0005. I dont shoot in real competitions, just against family and friends.

I did read stowaways #50 post about rim thickness. Then his #57 post about just buying expensive ammo. I am trying to achieve max accuracy with the cheapest ammo. One might say getting the most bang for my buck. Haha
 
The whole post from Stowaway includes some excellent vids of even 'quality' ammo being subjected to rotational tests. Even 'mis-aligned' bullets will throw your shots, so maybe checking that would help? i just check for loose bullets (wiggly) and 'nicked' ones. There's YT vids showing how small nicks can affect aerodynamics and bullet flight (slo-mo corkscrew flight).
What rifle are you using for your tests ?
Reading the whole series of posts from Stowaway is educational by itself - lots of things to check even with basic tools. Some of his visual comparisons are remarkable when seen in his testing equipment. I've never found out but he may be an engineer with one of the Euro-mfrs ?
 
Sorting by either method helps, but not that much. It may have mattered more in the past. I sometimes shoot with a former Olympic shooter that told me pretty much everyone there was sorting by rim thickness. He's still got a very nice tool that makes the job super quick. Kind of makes me wonder if it did make more of a difference decades ago, but perhaps now not so much. In the end, it is still CCI SV that you're shooting, and it has all sorts of issues beyond just variance in the rims and weight. For one, I don't think their powder charges are terribly consistent. Whether or not you're saving money depends how you view things. It takes time to do, which has value. And if you now have a pile of 15-20% or whatever that don't pass muster, the remainder just got more expensive. For the record, if I get bored enough I have still been known to do it just to pass the time, hehe. But I don't usually go out of my way to sort. It is sometimes surprising to see how much variance there is in some really expensive ammo, and sometimes how little there is in some fairly cheap ammo. And yet, somehow, they both tend to shoot as their price tags would suggest. :)
 
Buck1950 said:
The whole post from Stowaway includes some excellent vids of even 'quality' ammo being subjected to rotational tests. Even 'mis-aligned' bullets will throw your shots, so maybe checking that would help? i just check for loose bullets (wiggly) and 'nicked' ones. There's YT vids showing how small nicks can affect aerodynamics and bullet flight (slo-mo corkscrew flight).
What rifle are you using for your tests ?
Reading the whole series of posts from Stowaway is educational by itself - lots of things to check even with basic tools. Some of his visual comparisons are remarkable when seen in his testing equipment. I've never found out but he may be an engineer with one of the Euro-mfrs ?
Click to expand...
I have a cz 455 and a tikka t1x. The trigger leaves alot to be desired in the cz, even with the spring being upgraded. I have two heavy barrels for it. The tikka is stock.

I dont mind to putter around, more so when winter is here. This will give me something to do on the cold days with little daylight.
 
I just sold my 455 SS Lux this spring. I had put the YoDave light spring in but could not get any of the roller-shims in. Is that what you changed in yours? I also Lightly polished any friction points with 1000g wet/dry paper and lube Very Lightly with Permatex Synthetic PTFE grease from CanTire. The trigger was under 2#, I forget exact #s. - https://www.canadiantire.ca/en/pdp/...e-tube-85-g-0280813p.html?rq=Car+Parts+Grease
 
Buck1950 said:
I just sold my 455 SS Lux this spring. I had put the YoDave light spring in but could not get any of the roller-shims in. Is that what you changed in yours? I also Lightly polished any friction points with 1000g wet/dry paper and lube Very Lightly with Permatex Synthetic PTFE grease from CanTire. The trigger was under 2#, I forget exact #s. - https://www.canadiantire.ca/en/pdp/...e-tube-85-g-0280813p.html?rq=Car+Parts+Grease
Click to expand...
I just did the trigger spring. It has a fair bit of creep. I have it in a MDT xrs stock and from what I have read the 455 stocks wont fit a 457 that is what is stopping me from getting the 457 currently.

The tikka has a good trigger, a little heavy in my opinion. It shoots better then the 455 to be honest.
 
Yes, if you have the MDT stock it would hurt to change to the 457 unless you could modify the MDT to fit it. I don't know how feasible that would be. Maybe you could selI the package with not too great a loss? I kept my 455 and bought a 457 VMTR, running them 'against' each other for a while. After a year or so, I chose to sell the 455. Partly as I couldn't get used to the Lux stock that forced me into a chin-weld even with very low rings on a 50mm scope. But the 457 was consistently a more accurate rifle with both using SK+ and SK- Rifle match. I'm not 'real good' but I often get 5-shot groups in the 0.3s with the 457, where I couldn't get there with the 455.
And I did 'striker profiling' on both rifles, altho I don't have 'firm numbers' proving it did any good. I didn't have chrony stats from 'Before' to look at, but for a half-hour's work it was a fun-fiddling project. Here's a thread that convinced me to go ahead. Perhaps that can fill some of your winter evenings?
https://www.rimfirecentral.com/threads/reshape-striker-cz-455.602579/#replies
 
I will give this firing pin profile a check. Seems pretty self explanatory, file off enough on the outside to bring the striker with in the edge of the brass.

I have tried alot of ammo and it seems to get flyers on all of them.

Types i have tried.
Eley Tenex, club, auto match, ultra and a few more i cant remember.
Rws Match
Sk match
Federal HV match
Aguilla super extra.
Norma
S and B
Cci Standard
Lapua (I dont remember the name though)

Probably if I added up all of the ammo that didn't work the 457 would have been paid for now. If i am shooting pests it is more then accurate, but paper shows the variance.
 
fugemall said:
I have started measuring rim thickness on my 22LR ammo.
Click to expand...

I did the same and posted my results on the RimfireCentral forum...

Measured some Lapua Center-X and although I have some good targets as a beginner, rim thickness varied from 0.0425" to 0.0455" of 20 rounds measured. Most were around 0.0435".

No idea yet if it makes a difference, but I came from a standards lab measurment world and taking measurements is relaxing, like going for a ride on the motorcycle or going to the range.
Click to expand...

I now have more than 2730 rounds through it and for some time now the bolt action is ultra-smooth with no hard chambering. Could be due to use or the thin coat of Bore-Tech super slippery grease I put on the bolt.

By the way, I am now using Norma TAC-22 for 35% the cost of the Lapua Center-X. I never measured the TAC-22 yet.
 
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