Chopping down a CZ 557 Varmint (.308w)

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Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 8:33 am

Hi,

I'm considering one of these as my next purchase to be used primarliy for centerfire hunting rifle (metallic silhouette), but I'd like to do the odd trek with it too:

CZ557VRT308.tag.0.png
CZ557VRT308.tag.0.png (81.7 KiB) Viewed 5839 times


(in case you want more info, here's a link to it's specs: http://cz-usa.com/product/cz-557-varmint/)

The only problem is would I need to shave 1.2kg of weight off it to comply with the rules (it weighs 5kg unscoped), but I really want to keep the walnut stock because I absolutely love the look and target ergonomics of it - (love me a nice target comb) .

I guess the first port of call would be to chop the barrel down; it's a 26" so I guess I'd need to take at least 1/4 of the barrel away, bringing it back to around 19". Possibly I could bore the stock as well to reduce some weight towards the rear.

Question: do you guys think this is a viable idea? And besides from the drop of velocity, how detrimental do you think such a cut would be to the rifle's harmonics (and subsequent accuracy)?

Any speculation is welcome.

In2.
Last edited by in2anity on 18 Sep 2017, 9:32 am, edited 2 times in total.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 8:41 am

Here's a concept pic at 18":

CZ557VRT308.tag.1.jpg
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 9:33 am

Mate... That is a nice looking rifle. I do think it looks a little weird with that stock and a short barrel.

When i chopped down my Howa heavy barrel it reduced weight LESS (edit) than i expected. From memory 6' chop only saved 120g or so!

This may be a case of "no free lunch". Maybe you are best off with one rifle fore target and one rifle for hunting.

In response to your question on harmonics, etc, you will find the shorter barrel is stiffer and so a good cut and crown will have no detrimental effect on precision and may improve it.

For an idea of what sort of velocity loss you'll get, look at this:
http://bulletin.accurateshooter.com/201 ... el-length/
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by bigpete » 18 Sep 2017, 9:39 am

As long as you keep the cut perfectly square or get it recrowned you'll lose no accuracy.
I've done it a few times with a hacksaw and lost no appreciable accuracy lol
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 9:52 am

Also, (best ask one of the silhouette guys, like GameRancher, but) i'm not sure that style of stock is best suited to off-hand shooting. More designed for prone & bench shooting.

I agree, i do like it too but maybe you are better off with a hunter weight rifle and trim the barrel of that down to shave a bit more weight for alpine work as well as stiffen the barrel up (shorter cylinder of the same diameter is stiffer). Might be better for both silhouette and mountain hunting with both stock and rifle weight better meeting requirements.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 10:04 am

Gwion wrote:Also, (best ask one of the silhouette guys, like GameRancher, but) i'm not sure that style of stock is best suited to off-hand shooting. More designed for prone & bench shooting.


What I'm comparing this 557 varmint stock to is my LA101 in walnut à la:

101.jpg
101.jpg (30.83 KiB) Viewed 5799 times


which I currently routinely use for rimfire silhouette. Going back to other people's sporter style stocks (and even my other rifles) just doesn't feel right anymore. IMO the high comb is well suited to the standing position where your head needs to be anchored nice and high and centred down the vertical axis of the barrel.
Last edited by in2anity on 18 Sep 2017, 10:22 am, edited 2 times in total.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 10:13 am

Gwion wrote:When i chopped down my Howa heavy barrel it rediced weight more than i expected. From memory 6' chop only saved 120g or so!


Did you mean to say it reduced less weight than expected? 120g for 6" is fairly dismal :(
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 11:10 am

bigpete wrote:As long as you keep the cut perfectly square or get it recrowned you'll lose no accuracy.
I've done it a few times with a hacksaw and lost no appreciable accuracy lol


How'd you ensure it was perfectly square only using a hacksaw?!
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 11:14 am

in2anity wrote:
Gwion wrote:When i chopped down my Howa heavy barrel it rediced weight more than i expected. From memory 6' chop only saved 120g or so!


Did you mean to say it reduced less weight than expected? 120g for 6" is fairly dismal :(


Ooops... yes. i mean't to say LESS weight. Will go back and edit now.
Yeah, it's a poultry gain (or loss) but it did balance the rifle for off hand shooting!
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 11:16 am

in2anity wrote:
Gwion wrote:Also, (best ask one of the silhouette guys, like GameRancher, but) i'm not sure that style of stock is best suited to off-hand shooting. More designed for prone & bench shooting.


What I'm comparing this 557 varmint stock to is my LA101 in walnut à la:

101.jpg


which I currently routinely use for rimfire silhouette. Going back to other people's sporter style stocks (and even my other rifles) just doesn't feel right anymore. IMO the high comb is well suited to the standing position where your head needs to be anchored nice and high and centred down the vertical axis of the barrel.


I'd be interested to try it but that wrist looks pretty bulky... like i said, just my impression; others will have a much better idea.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 11:19 am

1.2kg is a BIG weight loss program!!!
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 12:02 pm

Gwion wrote:1.2kg is a BIG weight loss program!!!


Yeah it is; perhaps a little too much to ask :crazy: I guess I could aim for the "Centrefire Silhouette Rifle" category which permits up to 4.6kg, that way I'd only have to lose around 800g. I've never actually participated in a centerfire silhouette match; is "Centrefire Silhouette Rifle" the most popular (centrefire) flavor anyway?
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Oaker260 » 18 Sep 2017, 12:39 pm

Gwion wrote:1.2kg is a BIG weight loss program!!!

N thats if the manufacturer is correct with there specs
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Oldbloke » 18 Sep 2017, 5:17 pm

bigpete wrote:As long as you keep the cut perfectly square or get it recrowned you'll lose no accuracy.
I've done it a few times with a hacksaw and lost no appreciable accuracy lol


Yep, cut it off, just square it of and counter sink in a lathe. Bobs your uncle.

I did a 22rf years ago. Cut off, square it off with a file and then counter sunk the crown using a piece of "pointed steel bar", and lapping paste. Shot better. :lol:
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 8:42 pm

Didn't consider doing it myself - but something like this fellas? https://youtu.be/b43odFm0mrI
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 18 Sep 2017, 8:55 pm

Or just spend $80 to get a proper cut and crown!
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 18 Sep 2017, 9:13 pm

Gwion wrote:Or just spend $80 to get a proper cut and crown!


Yeah it's a pricey bit of kit to botch - but unless I'm looking in the wrong places there doesn't seem to be a whole lot of respected smiths in the Sydney region... :(
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Supaduke » 18 Sep 2017, 11:01 pm

Seems like a path to nowhere. Buy a nice rifle and hack it to bits. What happens if you do all that and still don't make weight ?

I would be looking at more suitable options instead of trying to stuff a square peg into a round hole.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 19 Sep 2017, 12:08 pm

sungazer wrote:
in2anity wrote:
Gwion wrote:Or just spend $80 to get a proper cut and crown!


Yeah it's a pricey bit of kit to botch - but unless I'm looking in the wrong places there doesn't seem to be a whole lot of respected smiths in the Sydney region... :(


Well you could give LRP Solutions a call Matt Paroz he did several of the F Class rifles for the world championships in Canada this year. I can also personaly recommended him. He has both built and barrelled riffles for me, he stands behind his work like an old timer would.


Great; did not know about this guy; appreciated Sungazer :friends: I even work up here on the North Shore!
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by Gwion » 20 Sep 2017, 8:45 am

Supaduke wrote:Seems like a path to nowhere. Buy a nice rifle and hack it to bits. What happens if you do all that and still don't make weight ?

I would be looking at more suitable options instead of trying to stuff a square peg into a round hole.


Gotta say I do agree with this.
It is quite likely that losing that much weight on that rifle is undoable without ruining it.
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Re: Chopping down a CZ 557 Varmint (.308w)

Post by in2anity » 21 Sep 2017, 1:42 pm

I think it's clear that such a procedure would be a bad idea, so I think I'll abandon this one. Thanks to all for their contribution.
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