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  #61  
Old 07-20-2019, 08:48 PM
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Quote:
Originally Posted by Frontrange42 View Post
After a few of you guys mentioned the weak ignition that is prone to the 457 I thought I’d fix that before anything else. I read all the posts you fellas pointed me to and then some. So I clamped down the dremel with a cutoff wheel and advanced the striker in by hand. Much easier to make an accurate grind on small parts. Then cleaned it up with sharpening stone. It’s definetely not hitting on the rim anymore and the strike is visibly deeper. maybe good, maybe not
My idea is to keep rifle as is since last time I shot (except for new striker shape) and shoot a few groups with same sk standard plus I’ve been using. I want to see if striker reshape affected the groups. After that I’ll play with different types of material for pressure pad. I used about the densest rubber I could find (picture material like pond liner). Which I now hear doesn’t seem to be best for my thin barrel. Open cell rubber...neoprene!? Maybe sheet cork? I’ll try em all.
I should keep doing all this testing with the same sk standard plus, correct? Makes sense to me because it shows me what I’m doing to the rifle effects groups and not what the ammo is doing. So when I’m satisfied with pad position and material then I can test ammo, ammo, ammo! Or it could be that with every ammo I try I need to play with pad position again? I hope that’s not the case.

If all the ammo you’re shooting is SV and close in MV, then no- the G-spot is the same.

SK, CenterX & Midas+ historically all used the same lube, so only minimal seasoning should be necessary when swapping between grades.

20/20 hindsight is fun, but personally I think crediting the firing pin work alone is a gross oversimplification.

I’m pretty sure it’s a combination of improvements contributed in varying degrees by each step.
Don’t believe me? Remove the pressure pad and shoot some groups... the magic firing pin might well lose some of its luster.
The pillar bedding was not a wasted effort in any case, as you can now look to the future with confidence in expecting consistent performance between takedown & reassembly. Your rifle should be less sensitive to environmental factors, like humidity expanding wood and changing the contact pattern in the inletting.
With respect to materials for pressure pads- remember that I posted generalizations based on my own past experiences and I’ll reiterate- There are exceptions to every rule.

You have groups there that tell you the pressure pad position and material is Good. You can experiment and fine tune from there, but I’d test ammo more. In fact- I personally would have done quite a bit more testing/shooting between steps.

Couple of questions:

What Is the pull weight of your trigger?

What type of rest system are you using to shoot these groups?

What is the most accurate rifle you own?

What is your personal best group you have shot from 50 yards with any rifle?

I’m not trying to be critical here, just trying to get a gauge on your equipment and what other rifles you might be using as a basis for comparison in you’re safe.


I noticed that you are shooting a 457 American. Getting under MOA from standard sporter style rifle like that is actually a very very good result. I think you may find at this point but you are delving into the realm of the “Law of Diminishing Returns”.
It’s likely that some of the inconsistency you’re seeing it at this point is simply inherent to the entire system. Heavy taper and Varmint profile barrels are much more conducive to the accuracy you are looking for.


Also, when trying to squeeze all I can from my sporters, I often use a bag rider affixed to a swivel stud using a UTG Picatinny rail bipod adapter, less than $10 on Amazon.



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Last edited by DrGunner; 07-20-2019 at 09:31 PM.
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  #62  
Old 07-20-2019, 08:54 PM
fourbore
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Thank you. Excellent project. I am sure you have helped a lot of people here.
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  #63  
Old 07-20-2019, 11:11 PM
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Quote:
Originally Posted by DrGunner View Post
Quote:
Originally Posted by Frontrange42 View Post
After a few of you guys mentioned the weak ignition that is prone to the 457 I thought I’d fix that before anything else. I read all the posts you fellas pointed me to and then some. So I clamped down the dremel with a cutoff wheel and advanced the striker in by hand. Much easier to make an accurate grind on small parts. Then cleaned it up with sharpening stone. It’s definetely not hitting on the rim anymore and the strike is visibly deeper. maybe good, maybe not
My idea is to keep rifle as is since last time I shot (except for new striker shape) and shoot a few groups with same sk standard plus I’ve been using. I want to see if striker reshape affected the groups. After that I’ll play with different types of material for pressure pad. I used about the densest rubber I could find (picture material like pond liner). Which I now hear doesn’t seem to be best for my thin barrel. Open cell rubber...neoprene!? Maybe sheet cork? I’ll try em all.
I should keep doing all this testing with the same sk standard plus, correct? Makes sense to me because it shows me what I’m doing to the rifle effects groups and not what the ammo is doing. So when I’m satisfied with pad position and material then I can test ammo, ammo, ammo! Or it could be that with every ammo I try I need to play with pad position again? I hope that’s not the case.

If all the ammo you’re shooting is SV and close in MV, then no- the G-spot is the same.

SK, CenterX & Midas+ historically all used the same lube, so only minimal seasoning should be necessary when swapping between grades.

20/20 hindsight is fun, but personally I think crediting the firing pin work alone is a gross oversimplification.

I’m pretty sure it’s a combination of improvements contributed in varying degrees by each step.
Don’t believe me? Remove the pressure pad and shoot some groups... the magic firing pin might well lose some of its luster.
The pillar bedding was not a wasted effort in any case, as you can now look to the future with confidence in expecting consistent performance between takedown & reassembly. Your rifle should be less sensitive to environmental factors, like humidity expanding wood and changing the contact pattern in the inletting.
With respect to materials for pressure pads- remember that I posted generalizations based on my own past experiences and I’ll reiterate- There are exceptions to every rule.

You have groups there that tell you the pressure pad position and material is Good. You can experiment and fine tune from there, but I’d test ammo more. In fact- I ppersonally would have done quite a bit more testing/shooting between steps.

Couple of questions:

What Is the pull weight of your trigger?

What type of rest system are you using to shoot these groups?

What is the most accurate rifle you own?

What is your personal best group you have shot from 50 yards with any rifle?

I’m not trying to be critical here, just trying to get a gauge on your equipment and what other rifles you might be using as a basis for comparison in you’re safe.


I noticed that you are shooting a 457 American. Getting under MOA from standard sporter style rifle like that is actually a very very good result. I think you may find at this point but you are delving into the realm of the “Law of Diminishing Returns”.
It’s likely that some of the inconsistency you’re seeing it at this point is simply inherent to the entire system. Heavy taper and Varmint profile barrels are much more conducive to the accuracy you are looking for.


Also, when trying to squeeze all I can from my sporters, I often use a bag rider affixed to a swivel stud using a UTG Picatinny rail bipod adapter, less than $10 on Amazon.



DrGunner
By no means am I saying the firing pin reshape work is the magic fix. I know I’ve been building a complete system here, one step building on the next step. What I am saying is if I did each one of these steps to the original rifle, starting with .610” average group the firing pin modification would have taken the most inches off. That’s all... I know all of these steps work together to bring that group down even more.
My trigger weight is set to 1.1 oz. with the slightest bit of creep.
I’m shooting off a homemade portable bench with sandbag up front and sandbag at rear. Nothing fancy.
My most accurate rifle? Well shoot doc because of you and others it’s a CZ 457 American! It’s all relative I think. I have a .22-250 that groups at 3/8” consistently at 100 yards with proper brass prep, and a carefully worked up load of H380. Is that more accurate than a .22 lr. that shoots .384” at 50yds?
My best group at 50yds was probably shot today. I can’t say I’ve ever messed with 50 yds. before. I’d say most of .22 lr. shooting was done at 30 yds. back in the day with my dad and grandad. Thats also the only competitive shooting I’ve ever done.
As for the bag rider.... well I’ve heard that term thrown around here and thought it was some kind of slang. After seeing your pic it’s not what I thought (I was way off). I’m not sure how it works though?
I’m not trying to shoot benchrest tiny groups here. I’m perfectly fine with what I got now. I was only hoping for 1/2” consistently. I do get a bit carried away and try to push it. I think any smaller and my shooting ability becomes a real a factor and not the equipment.
Let me ask you a question: Do you believe the average shooter can shoot a .400” 5 shot group at 50 yds. given rifle and ammo that is capable? This is off of sandbags and with a 20x scope of course. I believe they could and doesn’t take much skill. You start getting down into smaller group sizes and that’s when all kinds of benchrest skills come into play. I’ll be the first to admit I don’t know anything about those type of skills.
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  #64  
Old 07-21-2019, 12:41 AM
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Quote:
Originally Posted by Frontrange42 View Post
By no means am I saying the firing pin reshape work is the magic fix. I know Iíve been building a complete system here, one step building on the next step. What I am saying is if I did each one of these steps to the original rifle, starting with .610Ē average group the firing pin modification would have taken the most inches off. Thatís all... I know all of these steps work together to bring that group down even more.
My trigger weight is set to 1.1 oz. with the slightest bit of creep.
Iím shooting off a homemade portable bench with sandbag up front and sandbag at rear. Nothing fancy.
My most accurate rifle? Well shoot doc because of you and others itís a CZ 457 American! Itís all relative I think. I have a .22-250 that groups at 3/8Ē consistently at 100 yards with proper brass prep, and a carefully worked up load of H380. Is that more accurate than a .22 lr. that shoots .384Ē at 50yds?
My best group at 50yds was probably shot today. I canít say Iíve ever messed with 50 yds. before. Iíd say most of .22 lr. shooting was done at 30 yds. back in the day with my dad and grandad. Thats also the only competitive shooting Iíve ever done.
As for the bag rider.... well Iíve heard that term thrown around here and thought it was some kind of slang. After seeing your pic itís not what I thought (I was way off). Iím not sure how it works though?
Iím not trying to shoot benchrest tiny groups here. Iím perfectly fine with what I got now. I was only hoping for 1/2Ē consistently. I do get a bit carried away and try to push it. I think any smaller and my shooting ability becomes a real a factor and not the equipment.
Let me ask you a question: Do you believe the average shooter can shoot a .400Ē 5 shot group at 50 yds. given rifle and ammo that is capable? This is off of sandbags and with a 20x scope of course. I believe they could and doesnít take much skill. You start getting down into smaller group sizes and thatís when all kinds of benchrest skills come into play. Iíll be the first to admit I donít know anything about those type of skills.
Sounds like youíve got the right set of expectations- it wasnít just your post that alluded to the firing pin profile as having the most substantial effect- and sorry if I came off as snarky- that was not my intent. Without a Time Machine, there really is no way to tell which of the steps that you took were the most beneficial, but if I had to guess based on my experience tuning, I would still say that the pillar bedding and pressure pad probably did more than the firing pin profile despite what your groups are showing you now. The only way to prove the converse now would be to go back in time and do everything in reverse order, LOL.


Wouldnít it be sweet if we could load our own .22, and work up a fave recipe like your .22-250? I have a Core 15 VTP II 20Ē Stainless Match AR that shoots MOA to 300 so far. Core 15ís blurb on that rifle CLAIMS itíll hold MOA to 500 with the right load. I have yet to test mine that far, and my current heavy bullet recipe seems to come apart @ 350 and beyond. Judging by the impact holes, Iím thinking the 70-80 grain boat tails Iím using are starting to yaw past 300 and likely tumble beyond 350. I need to try lighter bullets or go hotter to stabilize them. I digress...


IMO, thereís nothing wrong with TRYING to squeeze BR accuracy out of a sporter- by using contrivances like the bag rider pictured above to alter/improve some of the design characteristics that make sporter stocks difficult to shoot groups with in the first place.

Now to answer your question Ė

I will need to make a qualification based on how you worded it. Do I think that the ďaverage shooterĒ can shoot .400 ďgiven that rifle and ammo are capable...Ē

To that, I would have to say yes.

That said, Iím not sure that I would classify your set up as ďcapableĒ to the degree that you could sit down a random group of average Joeís and get the desired result.
Add a Varmint barrel and bag rider to the ďcapableĒ definition & Ill agree.
Bottom line- Iím not trying to disparage you in any way- quite the contrary. The truth is, a sporter style stock and pencil taper barrel are about the hardest to shoot groups with. It takes practice, and skill.

You shooting a 457 American off of sandbags to .384Ē tells me two things Ė

1) I believe that you are better than an average shooter, and

2) I believe that your rifle, set up with a bag rider on a mechanical front rest and Protektor 13B tall bunny ear rear bag, with more ammo and lot testing can probably manage groups of .250Ē @ 50 yards. It would likely still average in the .3- 4Ē range, but Iíd bet itís capable of more than it has shown you so far.

Until you have tried a bag rider, you will not know how much stability they provide, substantially reducing canting of the rifle. You are simply modifying the rounded contour on the bottom of the foreend of the rifle into a nice flat plane that is parallel to the bore.

Hereís what I attach to the sling swivel stud:



The bag rider itself is easy enough to make, a block of wood and the bottom half of some cheapie scope rings:





I posted a thread on how to make these many years ago, Iíd have to do some serious digging to find it. Pretty self-explanatory from the photos. The UTG adapter is an easy way temporarily attach a bag rider to any sporter stock. They naturally adapt to any stock that already has a Picatinny rail in place such as an AR 15.


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  #65  
Old 07-21-2019, 01:32 PM
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So, if I have this right. The bag riders main purpose is to keep the vertical crosshairs exactly plumb for every shot?
What I’ve been doing is setting up my cardboard box then taking a level to mark a plumb line on it. I then staple my target paper right along this line. When I shoot ive been making sure my vertical crosshair is parallel with the edge of the paper.
I can see how the bag rider accomplishes this much more exactly given your front rest is dead level. I see the leveling bubble you have on your front rest.
I’m always having to reshape my front bag because the sand settles. This can’t be good for the level of consistency you (DrGunner) speak of. I’ll read up on these bag riders and educate myself on their use.
I’m smart enough to know I don’t have enough knowledge on the subject to debate with you as to how much the firing pin did for this rifle. I do know that my rifle is much more accurate now than it was before and I’m very pleased with it. In fact I’m already considering another cz 457. A non sporter model. But which one? That’s probably material for a different post, but would definitely appreciate your input on that when the time comes.
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  #66  
Old 07-21-2019, 09:38 PM
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If you get another 457 and you are looking for accuracy stay with a 22LR. That goes for any rifle made. 17hmr ammo is so inconsistent it will give you fits. It does me for that reason. I still love the caliber for plinking and hunting small critters but it's not for match style accuracy. 22 Mag is similar with inherently less accuracy than the 17hmr. Its why the 457 Mtr and 457 manners tactical trainers are only offered in 22lr.
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Old 07-21-2019, 11:16 PM
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If you get another 457 and you are looking for accuracy stay with a 22LR. That goes for any rifle made. 17hmr ammo is so inconsistent it will give you fits. It does me for that reason. I still love the caliber for plinking and hunting small critters but it's not for match style accuracy. 22 Mag is similar with inherently less accuracy than the 17hmr. Its why the 457 Mtr and 457 manners tactical trainers are only offered in 22lr.
No worries there. I have zero interest in those cartridges.
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  #68  
Old 07-22-2019, 01:12 AM
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Originally Posted by Frontrange42 View Post
So, if I have this right. The bag riders main purpose is to keep the vertical crosshairs exactly plumb for every shot?
What Iíve been doing is setting up my cardboard box then taking a level to mark a plumb line on it. I then staple my target paper right along this line. When I shoot ive been making sure my vertical crosshair is parallel with the edge of the paper.
I can see how the bag rider accomplishes this much more exactly given your front rest is dead level. I see the leveling bubble you have on your front rest.
Iím always having to reshape my front bag because the sand settles. This canít be good for the level of consistency you (DrGunner) speak of. Iíll read up on these bag riders and educate myself on their use.
Iím smart enough to know I donít have enough knowledge on the subject to debate with you as to how much the firing pin did for this rifle. I do know that my rifle is much more accurate now than it was before and Iím very pleased with it. In fact Iím already considering another cz 457. A non sporter model. But which one? Thatís probably material for a different post, but would definitely appreciate your input on that when the time comes.
A bag rider would help with stability off of sandbags as well, although it shines best when using a 3Ē flat rest bag for a BR stock. One thing I have noted- while most of my heavy barrel bench rest rigs shoot best under free recoil conditions, the vast majority of the sporter rifles that Iíve shot, owned or tuned for others definitely seem to prefer some downward pressure on the foreend of the rifle holding them into the rest or bag. This is one area that the bag rider really shines, as itís easy to get a grip on the foreend without touching the barrel. You simply place your left thumb on top of the left side of the bag rider and hold it in place for each shot.

I probably have an extra bag rider laying around. If you want one, send me a PM and Iíll ship it to you, freebie!

Iím partial to CZ452s... I have a Scout, a Silhouette, a Style and a Varmint. If you can lay your hands on a 452 Varmint, that would be my recommendation. They pop up for sale here in there from time to time, I saw a new one selling the trading post for $600 about a month ago, and a used one sold for $400.

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  #69  
Old 07-22-2019, 10:03 AM
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I probably have an extra bag rider laying around. If you want one, send me a PM and Iíll ship it to you, freebie!

DrGunner
Okay besides those bag riders being slicker than snot, you're a pretty good guy.
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Old 07-23-2019, 11:17 AM
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Okay besides those bag riders being slicker than snot, you're a pretty good guy.
Thanks, Master Yoda.

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