Thanks Don...now that most of the tuner work is out of the way, I'm having some fun. Using a lot less ammo too.
Printable View
Thanks Don...now that most of the tuner work is out of the way, I'm having some fun. Using a lot less ammo too.
I got to the range today.
Wind was 2mph or less. Occasional gusts up to maybe 5 mph which I could wait out easily.
Sunny and temp of 78 degrees. Calculated speed of sound 1135fps.
I was wanting to confirm the results I achieved last trip.
I took the chronograph with me and tested the speeds from the MTR and the 452 trainer with the new order of Eley Tenex that showed up yesterday.
I also tested the Eley Match in the 452 Trainer since I had not run it over the chrono before.
The new Eley Tenex was rated at 1043 fps. It chronoed at 1142fps average velocity in the MTR. The SD and Extreme spreads were similar to what the other Tenex lots have been.
Even though it showed supersonic(and there was a sharp crack when it fired), it grouped very well. At least as good as the best I tested before.
In the 452 Trainer, the velocities averaged 1098fps. SD was 4.5 and the spread was 11fps.
The groups were excellent but not significantly better than the Eley Match.
I had hoped this lot would be significantly slower than the other lots I have but it surely isn't. It is a bit faster even. It didn't post a single chrono reading under the sonic level. I was getting right at 100 fps more than what the advertised velocity was in the MTR.
Either my chrono is wrong or the ammo isn't as advertised.
This is what the 452 was doing with the Eley Match and the Tenex. The MTR was doing similar. Shot at 50 yards.
Attachment 285510
The inside edge of the inner ring is exactly the size of a dime.
I am very pleased with the accuracy and consistency I am getting now.
Now if I could find out if the velocity discrepancy is my chrono or the ammunition I would feel better about things.
The new Caldwell front rest arrived today just after I got home from the range. Oh well, it will be ready fro the next trip.
I read an article about using tuners on the rimfireaccuracy site. They were talking about a guy who did studies on this and came up with a formulas about where to set the tuner to get the best harmonics. The formulas are called Purdy's Prescription.
It had to do with setting up the final harmonic to occur at the end of the tuner and could be calculated. Many people on that site swear by it. Apparently it works well enough that they start there and seldom adjust it more than a click or two either way.
Here are the formulas. This applies to a Herrell tuner such as the one you have .
Barrel Length (BL) = length of naked barrel from breach face to crowned muzzle.
Physical Length (PL) = length of barrel/tuner/slide combination from breach face to end of tuner or slide.
For standard H/H Tuner:
(BL/8 x 9) - 0.45" = PL
PL - BL = Tuner Length
For H/H Tuner w/ J&J Slide:
(BL/8 x 11) - 0.45" = PL
PL - BL - 6.125" = Tuner Length
For H/H Tuner w/ Parallel Noodle:
(BL/2 x 3) - 0.45" = PL
PL - BL - 9.125" = Tuner Length
tazman I just saw this and thought this is what Charlie is looking for, I found this at rimfire central. So I called OS OK up and send him the link, so I'll put the link up for everyone. Good work tazman!
https://www.rimfirecentral.com/forum...d.php?t=544427
It's been a couple weeks since I posted here... As most of you know, I've been busy with that 'Torpedo Tuner' over in this thread... https://castboolits.gunloads.com/sho...BE-at-50-yards. New to using a 'PEEP & GLOBE' at 50 yards...
Since I have some time off that project while Harry Tobin machines me a bushing (thank you again Harry!), I thought I'd re-address a Monkey that's been on my back...it is the 'Life Saver Challenge' over on TRN (the Reloaders Network .com on their Discord channel)
One of the fellas came up with the idea of super gluing 10 Life Savers to a card and trying to get a shot through the center of one at 50 yards.
I tried several times and busted up a lot of life savers and then got busy with the MKII and that new tuner idea I had...haven't been back to the challenge since but it's been hanging over my head to get it done.
This morning I got out early while the wind was absolutely dead calm...I strung a string between my 50 yard bench and the backstop to determine the angle I am shooting at. The bench turns out 15º off to the right. I had to make a little temporary target holder to get that card of life savers facing me...that hole in the Life Saver is .285" and I need to be shooting square onto the targets.
https://i.imgur.com/ryoU40g.jpg
https://i.imgur.com/yS3HZwM.jpg
It turns out that the target backstop is a little higher than my bench but I couldn't do anything about that but cross my fingers.
The backstop is on the right side of the bubble...
https://i.imgur.com/oaDUDm8.jpg
Next was to hot glue a target card holder together that I could screw to the backstop...
https://i.imgur.com/YfHIAaa.jpg
Then it was time to get down to business...I made my 'warmer shots' & a couple scope adjustments and then moved over to the life savers.
Danged if I didn't get the first shot in there!
I thought at first, when the life saver didn't scatter all over the place that I had missed the entire card. I walked up to the butt to take a look...how's about them Apples?
https://i.imgur.com/z8yVvyX.jpg
Well, after standing there a few minutes and admiring that hole in a hole, I walked back to complete the whole card.
Danged if I didn't slip another shot right through the center...I never was so flabbergasted in my life!
https://i.imgur.com/GLSkpcH.jpg
https://i.imgur.com/8sd6wY9.jpg
Got that Monkey off my back, think I'll shoot for the pleasure of shooting this week and up until I get that bushing back from Harry Tobin...then I'll be back over in the New to using a 'PEEP & GLOBE' at 50 yards... and working on that Mercury filled 'Torpedo Tuner'.
PS . . . I think the next thing I should do today is go buy a lottery ticket! ... :bigsmyl2:
That is amazing! 20% through the hole.
You are a tenacious bastard....and hard work pays off
My hat is off to you.
Thanks Harry & Don... I appreciate it...but it sure does help to have a precision rifle that runs well...I was just the goof behind the scope using his 'bugger hook'. :bigsmyl2:
Good stuff, OS! I do hope you will be framing those. Or a reasonable facsimile ie a photo. :mrgreen:
I need to get ready for this coming Sunday at the range. I'm going to be playing with paper patch boolits in my well worn 303 carbine. But not the whole time. I'll do some more 22 shooting too, naturally. I haven't actually looked for life savers. The first and last time I ever saw them was as a school kid. That wasn't too recently. :roll:
303Guy...I think this was the 6'th attempt, not sure but I know I went through 1 bag of those life savers...killed every one of them. I'll tell you how confident I was, I bought 2 more bags of them thinking that'll be enough to get this job done. In other words...I wasn't sure I'd ever do it.
Funny you should mention framing them, I had the same thoughts. This is the toughest challenge I ever tried.
I went to a informal competition today and shot well. All my misses were just barely scratching the outside of the ring enough to cost me points.
25 shots that, center to center, measured under .5 inches. If they had been using the ARA Factory class target, I would have shot a perfect score.
As it was I had 4 shots that barely cut the lower score ring and cost me points.
A little more work yet to do.
By the way, I shot the 452 trainer today with Eley Match black box.
Got my backside kicked. Somebody fired a perfect score.
Congratulations tazman... [smilie=p:
It sure pays off at times when you work so hard for something...way to go man!
Great shooting OZ. Having seen the pics I am in awe.
Take Care
Bob
I was watching a video on youtube about finding the best ammo for your rifle and heard something interesting.
The expert said he pulled apart some popular match grade ammunition(didn't name the brand) and found that the powder didn't even come close to filling the case.
This suggests to me that we might want to experiment with powder position when loading ammo into the rifle to get the powder position consistent.
Might be something to experiment with using a chrono to see if it helps with consistency.
I took some time this morning to weigh and measure rim thickness on some Eley Match and some Eley Tenex.
Complete waste of time.
I weighed ten bullets of each type, All of the corresponding bullets weighed exactly the same as nearly as I can measure with my RCBS beam scale. I used a tool I purchased to measure rim thickness. All the rims measured exactly the same.
Sometimes I wonder why I bother testing the good stuff.
I think I can do it with my match rifle by holding the cartridge tip up before I lay it softly on the feed ramp(single shot loading adapter) and push it into the chamber with my thumb. That should give the powder a consistent position in the case.
I don't need to move the rifle using that method.
I already do part of that method so changing it a bit to be consistent wouldn't be much of a change.
I could also hold the cartridge tip down before loading. Might be interesting to see if there is an appreciable difference.
I mentioned the squirrel rifle just for the ease of getting accurate numbers easily & for knowing for sure the powder will stay put...
I was thinking how I might load using the magazine sled (don't use a magazine in the CZ or the Sav.).
If powder against the base/primer turns out the best numbers, I'm afraid that when closing the bolt, that the jarring of the last little distance into battery would spread the powder across the length of the case...or...if I were to push the round completely into the chamber, the extractor snapping over the rim as the bolt goes into full lock-up/battery, might spread the powder in the same way.
Well, all that can be figured out later, I'm interested in seeing what the numbers say...that's a great idea tazman. Once the numbers are known, it'll be easy to tell whether or not the method of loading into chamber is working or not.
I went to the range this morning and took my chronograph with me. I did the testing on Eley Match with the tip up and tip down, as well as groups shot at the same time. All ammunition was from the same box of 50 rounds.
I fired the rifle about 50 shots before I did any of the testing to warm up the rifle and season the bore. It was very humid this morning. I had to wait a while and wipe the condensation off the rifle and scope lenses before I could shoot.
The temperature was 82-83 degrees so the speed of sound should have been around 1140fps.
The chronograph was about 4 feet from the muzzle.
The tip down was the easiest to do so I did it first.
Average was 1136
ES was 12
SD was 4.2
Tip up required some gun movement in order to maintain the powder position. I tipped the rifle vertical, loaded the round into the chamber with my thumb, closed the bolt, and gently lowered the rifle back onto the bag. Not perfect but was the best I could come up with.
Average was 1140
ES was 20
SD was 6.3
The groups were noticeably better with the tip down and there was a slight impact point shift between the techniques. The tip down method is what most closely resembles my standard method of loading so I will stick with that.
Later, when I was shooting for practice and "score", I had something happen I have never seen before. The eleventh round in a string of Tenex may have ruptured the rim, making the bolt difficult to open and blowing powder into the action. The bullet lodged in the barrel about 2 inches from the chamber.
I had to force the bolt handle back hard to get the case out of the chamber. When it opened, the case went flying off into the grass so I could not find it.
I was able to push the bullet out of the barrel with a cleaning rod easily enough but the action was difficult to clean up. Apparently, Eley uses a ball powder of some type in their Tenex rounds.
Here is a picture of the bullet.Attachment 286526
The ridge around the nose is from the cleaning rod pushing out the bullet.
I had to fire nearly 40 rounds through the rifle before it began grouping properly again. Now I need to take the rifle and the bolt apart and do a thorough cleaning to get all that unburned powder out of the action.
Fortunately, this happened after the testing or the results would be suspect.