457 MTR: Crown Re-Cut and Re-Pillar Bedding?

1387 Views 31 Replies 16 Participants Last post by Rider47, 2 d ago

Rider47

Discussion Starter · 18 d ago

1. Has anyone had the crown on their 457 / 457 MTR re-cut with a lathe? Before and after results? My new 457 MTR appears to have a ~45dgree angle crown cut with a reamer. (Recutting the crown with a lathe - 11 degree or recessed 0 degree - is allowed in ARA Factory class.)

2. Has anyone drilled out the factory pillars and replaced them with metal pillars and epoxy beddded the action? Before and after results? (Also permitted in ARA factory class.) My new 457 MTR shows the reported widely varying precision responses to different action torque values, which seems to scream for metal pillar with epoxy bedding. Or is this differing response to various torque values a fortuitous tuning mechanism?

Responses from those with actual hands-on experience appreciated . . .

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wscott9689

· #2 · 18 d ago

I am also interested in this info. I just started shooting ARA with my MTR and have wondering if it would be worth doing either/both of these.

Rider47

Discussion Starter · #3 · 17 d ago

I usually make my own pillars from aluminum round stock as I've found the commercially available pillars are too small in diameter. This time I ordered the set, along with the "upgraded" screws, from Pete's Pillars. They were ordered on 5/8 (no out-of-stock indication) and I received a shipping notice email on 5/9. However, the provided tracking # shows that while a label was created, the USPS had not received the item by today 5/16. I emailed PP yesterday but have not had any response yet. I'm not sure what's going on, and the pillars could show up tomorrow, but for the time being, I wouldn't recommend ordering these from PP.

I will be installing aluminum pillars in my 457 MTR (possibly homemade) and will report back issues and results.

1Merlin

· #4 · 17 d ago

PP was a little slow with mine also but did deliver a good product. This was last week....

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Booner1334

· #5 · 17 d ago

I have a 457 Varmint MTR-the wood stock one.
I didn't re-crown the barrel but I did use a brass spud from Brownell's with some mild abrasive applied to it to smooth any machining marks at the muzzle. I do this to most of my guns and have never seen adverse reactions as far as accuracy.

I bedded the action and the first inch of the barrel channel. Since the whole action is bedded, I didn't see any reason for adding pillars, as it's not like there's a lot of recoil to deal with. I did glue in the recoil lug that's on the tang. Since I have a wooden stock, I removed about 1/8th inch of wood on the interior of the stock, so I had a solid amount of bedding laid down. My action screws are torqued to 18-inch pounds. I don't know what you're trying to accomplish with your bedding; I did mine because it's a wooden stock and I live in a humid part of the country, so I didn't want and stock movement.

The biggest improvement in accuracy; relentless searching for that magic lot of ammo and wind calls.

Good luck.

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Rider47

Discussion Starter · #6 · 16 d ago

Below is an image of the front factory pillar in my 457 VMTR.

Of note:
1 - the pillar machining seem to have been part of the action/stock inletting process
2 - from the clearly seen imprint/depression of the action on top of the pillar, the pillar material compresses under pressure and does not reform
While this pillar and bedding are worlds better than having the action bolted into pure wood, it is a far cry from optimal for precision, which is the goal.

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cwhuebner

· #7 · 16 d ago (Edited)

I've pillar bedded three CZ's and one T1X. Pete's Pillars for one CZ but 13MM X 7MM aluminum tubing for rest. Used the Pete's as template for the 457's. Tikka no need. All guns now shoot best with 18-20 in/lb. torque.

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Finnerman

· #8 · 15 d ago

cwhuebner said:
I've pillar bedded three CZ's and one T1X. Pete's Pillars for one CZ but 13MM X 7MM aluminum tubing for rest. Used the Pete's as template for the 457's. Tikka no need. All guns now shoot best with 18-20 in/lb. torque.

Rider47 said:
Below is an image of the front factory pillar in my 457 VMTR.

Of note:
1 - the pillar machining seem to have been part of the action/stock inletting process
2 - from the clearly seen imprint/depression of the action on top of the pillar, the pillar material compresses under pressure and does not reform
While this pillar and bedding are worlds better than having the action bolted into pure wood, it is a far cry from optimal for precision, which is the goal.

This is on my short list of things to do to my AT1. T

Finnerman

· #9 · 15 d ago

Bedding is on my short list of things to learn. Thanks for sharing.

Rider47

Discussion Starter · #10 · 15 d ago

4

After 10 days with no product shipped and 3 days with no response to multiple emails I was fed up with Pete's Pillars and decided to make and install my own. (FYI - Response from PP came after I sent a cancel order email - which was not acknowledged.) The aluminum pillars were made from 1/2" round stock and contoured to fit the action, although not with the exact same shape as the CZ pillars.
Shown below are the pillars attached to the action. I made each pillar about .030" longer than the originals to leave extra space for epoxy when bedded.

The removal the existing plastic pillars was quite easy (I started with a 3/8" drill and then used a dremelish tool) and this was one of the easiest rifles to make pillar holes as I just had to remove plastic until wood appeared.

The pillars were then install using Devcon Steel Epoxy.

I have not yet bedded the rest of the action as I usually do pillar/epoxy bedding as a two stage process. The pillars look okay and seem to function well with the rifle reassembled.

I won't have time to bed the action until late next week, so will shoot the rifle as is with the action supported by just the two pillars (currently about a .030" gap to the wood). I will also have to test different ammo and different torque values AGAIN. This will require very low wind conditions and will use up precious ammo. I'll likely be able to report back results sometime next week.

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Rider47

Discussion Starter · #11 · 15 d ago

2

Oh yeah I forgot - I also decided to re-crown the barrel to a recessed 0-degree (flat) cut crown, removing just enough barrel to eliminate the 45-ish degree factory crown.

Factory crown

Re-cut crown

Please note I am NOT a machinist or a gunsmith. Just a guy who is somewhat handy and not afraid to try stuff. I do have a mini-lathe and although I'm pretty lousy with it, I sometimes get things done more-or-less how I planned. Usually after a few failures. I'm not sure about this crown job as my lathe will not hold .000X"s, and barely .001"s, but there is a gunsmith nearby who can re-cut this properly if it doesn't work out.

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cwhuebner

· #12 · 14 d ago

Looking forward to shooting reports.
I did same procedure for pillar bedding my AT-1 24". Shoots so well I skipped the action bedding. Retesting torque values only took a box and a half of SK Match and the sweet spot was at 20 in/lb.

djdilliodon

· #13 · 13 d ago

Recutting the crown can yield positive results or no improvement at all. It all depends on how good the factory barrel is from the start. Bore scoping the barrel and slugging it can help determine if the barrel is worth investing in a recrown. If it slugs poorly, has issues inside, or both, it’s best to save your money and not invest at all. Pillar and glass bedding is always worth doing regardless. Just don’t bed any part of the barrel incase you have to change it.

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Rider47

Discussion Starter · #14 · 12 d ago

Okay, some early post-modification results and observations . . .
Apologies in advance for the longish post.)

Based on very limited shooting of this rifle as-was out of the box and after each “improvement” (trigger, crown, pillars), using a variety of quality ammo I have on hand for use in my UL rifle (Eley Match, Lapua C-X, M+, X-ACT) I was coming to the conclusion that I simply did not win, or even place, in the “barrel lottery”. Results were unacceptably poor at worst, and inconsistent at best (especially with action screw torque changes). At the tail end of my last home testing in desperation I tried out some of my PRS rifle (10/22) ammo – SKLRM - and was surprised to see this stuff perform, if not well, at least better than previously tested more expensive ammo. I then left my house for 2 days to help set up a PRS match, shoot the PRS match on Saturday and then shoot some BR matches the following day. After PRS set-up was complete a couple of guys went to the 50 yard range and I had an opportunity to shoot a brand new Bergara. Five shots went into one hole – very nice! I then took out my VMTR and with the same SKLRM I used at home, and shot a 1”+ group. I was not happy, and you could have bought this rifle from me at a steep discount.

Flash forward to Sunday morning where I entered a local ARA Factory (outdoor) match, just to get in some rounds, with low expectations. Only 10 shooters, and at least six CZ 457 VMTR’s, along with a couple of Bergara’s on the line.

FYI – I shot using a homemade wide stance bipod and a soft bunny ear rear bag. I borrowed a few mags from a buddy and struggled with reloading during the match (I shoot a LOT of sighters) and other issues such a slimy hands (love that SK ammo). I also tested my modified trigger with a borrowed gauge which read about ¾ of a pound (12oz.) and while I question the accuracy of this tool at that low end of the force scale, I believe the trigger is solidly sub-1#.

During the match I could make no sense of the wind conditions, with the flags switching constantly and even spinning around in circles, and I thought I’d shot a pretty crappy 3 cards. But – when I briefly got a particular wind condition, the holes appeared where they should be. My crappy scores (I will not reveal these they are so bad) turned out to be good enough to edge out the second place shooter for a win. Go figgur . . .

So I would have to say the modifications I’ve made seem, at least at this stage, and still with very limited testing, to at best, have somewhat improved precision – or at least not harmed it – of course - WITH THE RIGHT AMMO. (Duh.) I am now faced with a somewhat tricky decision. If the rifle is shooting well with just the aluminum pillars, suspended ~.030” above the rifle stock with no action bedding, do I not mess with what’s working? Or go ahead with the planned epoxy bedding of the action? Hmmmm . . .

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mick l

· #15 · 8 d ago

Rider47 said:
I usually make my own pillars from aluminum round stock as I've found the commercially available pillars are too small in diameter. This time I ordered the set, along with the "upgraded" screws, from Pete's Pillars. They were ordered on 5/8 (no out-of-stock indication) and I received a shipping notice email on 5/9. However, the provided tracking # shows that while a label was created, the USPS had not received the item by today 5/16. I emailed PP yesterday but have not had any response yet. I'm not sure what's going on, and the pillars could show up tomorrow, but for the time being, I wouldn't recommend ordering these from PP.

I will be installing aluminum pillars in my 457 MTR (possibly homemade) and will report back issues and results.

same issue i had with the wait and no contact so i cancelled and was charged 20% , oh well it will only happen once

Rider47

Discussion Starter · #16 · 8 d ago

I just looked at my VISA account and see the same thing. Pete's Pillar's charged me $31.99 on 5/8, immediately upon ordering. On 5/9 they sent a "Your order has shipped" email with tracking. NO ORDER HAD BEEN SHIPPED. Tracking showed "label created" only for the next week+. After many days and repeated emails requesting contact regarding the status of the order I finally sent an email cancelling the order. I finally got a response and confirmation of my cancellation and credit. Of $25.59, not $31.99. What a business model - Charge people for an ordered product - send a product shipped notice, but DO NOT SHIP - refuse to acknowledge repeated requests for information on the order - charge 20% when they eventually cancel the order. I'm with mick I above - I will never order from Pete's Pillars again.

Reactions: 1

Al the Infidel

· #17 · 7 d ago

Rider47 said:
Okay, some early post-modification results and observations . . .
Apologies in advance for the longish post.)

Based on very limited shooting of this rifle as-was out of the box and after each “improvement” (trigger, crown, pillars), using a variety of quality ammo I have on hand for use in my UL rifle (Eley Match, Lapua C-X, M+, X-ACT) I was coming to the conclusion that I simply did not win, or even place, in the “barrel lottery”. Results were unacceptably poor at worst, and inconsistent at best (especially with action screw torque changes). At the tail end of my last home testing in desperation I tried out some of my PRS rifle (10/22) ammo – SKLRM - and was surprised to see this stuff perform, if not well, at least better than previously tested more expensive ammo. I then left my house for 2 days to help set up a PRS match, shoot the PRS match on Saturday and then shoot some BR matches the following day. After PRS set-up was complete a couple of guys went to the 50 yard range and I had an opportunity to shoot a brand new Bergara. Five shots went into one hole – very nice! I then took out my VMTR and with the same SKLRM I used at home, and shot a 1”+ group. I was not happy, and you could have bought this rifle from me at a steep discount.

Flash forward to Sunday morning where I entered a local ARA Factory (outdoor) match, just to get in some rounds, with low expectations. Only 10 shooters, and at least six CZ 457 VMTR’s, along with a couple of Bergara’s on the line.

FYI – I shot using a homemade wide stance bipod and a soft bunny ear rear bag. I borrowed a few mags from a buddy and struggled with reloading during the match (I shoot a LOT of sighters) and other issues such a slimy hands (love that SK ammo). I also tested my modified trigger with a borrowed gauge which read about ¾ of a pound (12oz.) and while I question the accuracy of this tool at that low end of the force scale, I believe the trigger is solidly sub-1#.

During the match I could make no sense of the wind conditions, with the flags switching constantly and even spinning around in circles, and I thought I’d shot a pretty crappy 3 cards. But – when I briefly got a particular wind condition, the holes appeared where they should be. My crappy scores (I will not reveal these they are so bad) turned out to be good enough to edge out the second place shooter for a win. Go figgur . . .

So I would have to say the modifications I’ve made seem, at least at this stage, and still with very limited testing, to at best, have somewhat improved precision – or at least not harmed it – of course - WITH THE RIGHT AMMO. (Duh.) I am now faced with a somewhat tricky decision. If the rifle is shooting well with just the aluminum pillars, suspended ~.030” above the rifle stock with no action bedding, do I not mess with what’s working? Or go ahead with the planned epoxy bedding of the action? Hmmmm . . .

Seeing you asked, bed it.

ZMan57

· #18 · 7 d ago

djdilliodon said:
Recutting the crown can yield positive results or no improvement at all. It all depends on how good the factory barrel is from the start. Bore scoping the barrel and slugging it can help determine if the barrel is worth investing in a recrown. If it slugs poorly, has issues inside, or both, it’s best to save your money and not invest at all. Pillar and glass bedding is always worth doing regardless. Just don’t bed any part of the barrel incase you have to change it.

…could you - or anyone 😊 - explain the process of slugging the barrel - in clinical detail?

TIA!😊

bumperm

· #19 · 7 d ago

I'm no expert, so there is that. I like to use air gun pellets for .22 or 17. Take a pellet and press the skirt against a ball bearing to expand the skirt a little (other round objects (pen cap, punch, Phillips screwdriver turned etc.) will do I'm sure. Use a suitable cleaning rod to slowly push the pellet through the bore from the breech end. This allows for a good sensitive tactile "feel" of the bore, including any added resistance if the muzzle end is chocked etc.

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flangster

· #20 · 7 d ago (Edited)

ZMan57 said:
…could you - or anyone 😊 - explain the process of slugging the barrel - in clinical detail?

TIA!😊

I will take a crack at it. Instructions for a boltie. For a 10/22, you'd need to remove the barrelfrom the action first. The folowing has worked on my CZs.

1. Clear your rifle.
2. Remove a bullet (slug) from its brass .22 lr case by wiggling it back and forth and then pulling it out of the case. Pliers may be necessary, but I am always suprised how loose .22 LR ammunition is in its initial setup compared to CF. Safely discard the powder.
3. Set up your rifle in a non-marring vise, with plenty of room behind the buttstock. Or, as I do, remove the barrelled action from the stock and clamp the barrel in the vise.
4. Remove the bolt.
5. Place the lead bullet you freed from its case in Step 1 in the breach.
6. With your cleaning rod (no jag), push the bullet through the bore. There will be the greatest resistance at the chamber lede, when the soft lead bullet is conforming to the lands. You want to exert an even pressure and try not to bend your cleaning rod.
7. During the process, pay attention to the physical feedback you are getting from the cleaning rod. As you push the bullet through the bore, you may feel tight or loose spots. You may feel a smooth, consistent surface. You may get "pulses." You can mark the cleaning rod with a Sharpie to get a sense of where in the barrel a particular condition occurs.
8. Congratulations.You have just slugged your barrel.

I usually have to repeat the process a couple of times (new bullet each time) to confirm what I am feeling. Together with a borescope, these are useful tools/methods for figuring out what's going on down there.

Good luck!

If the above is unclear, or if you learn better from pictures than words, you can search what I call The University of Youtube. I'm sure someone has posted a how-to video on this.

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