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Snayperskaya: I've had good luck with wrap on a refurb 91/30 that I was attempting to accurize but my 5 PU's all have pressure on the barrel at the forend tip which would seem to preclude any benefit from a wrap at the upper band. All 5 have fully floating barrel from reinforce to forend tip without any shims. 3 of them are non-refurbs and I must say the bedding on them is probably as good as or better than any WW2 military rifle I've owned. Frankly, even the 2 refurbs, with replacement stocks, are very well done and are accurate rifles.

Ruprecht
 

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I'd like to see a pic of that wrap if you can.... I do wrap mine there but if original it would be interesting...
Here you go mate, this is pretty much exactly as I found it first time I took the handguard off......it's not the cleanest and smells a bit and is quite fragile but I really don't want to replace it.When I refitted I just very lightly oiled it and put it back exactly where it was as I marked the barrel with a China marker at both ends of the wrap.

DSC_0001.jpg
 

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Discussion Starter #63
Here you go mate, this is pretty much exactly as I found it first time I took the handguard off......it's not the cleanest and smells a bit and is quite fragile but I really don't want to replace it.When I refitted I just very lightly oiled it and put it back exactly where it was as I marked the barrel with a China marker at both ends of the wrap.

View attachment 3707749
Beautiful, thank you for posting this!
 

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It think the barrel wrap gives a known pressure point in a specific area to dampen barrel harmonics.From what I gather some Mosins like a fully floated barrel whereas others don't.I had a standard infantry '39 Izhevsk 91/30 that wouldn't hold a half decent group so I shimmed it and added a wrap and the accuracy vastly improved and was consistent.....but......it took a bit of trial and error with the positioning on the wrap to find the "sweet spot", an inch or two either way made a noticeable difference.I think the wrap acts like a low tech version of the barrel tuning dampers that precision target shooters use.

I agree. That is traditional wisdom here. Apparently it is akin to the Boss system on a Winchester.
 

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The wrap at the front band, along with metal shims between the action and the stock, are supposed to 'free float' the barrel except for the wrap location. If you've ever examined the Finnish M39 or even the re-worked M91 rifles, you'll often find that the barrel doesn't touch the stock except at the nosecap (M39) or at the front band on the M91.
I wrapped a couple of my PU snipers at the front band and used metal shims to mimic this but for some reason the group size increased. Not sure why, but my '43 PU shoots better without the wrap treatment.
 

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The wrap at the front band, along with metal shims between the action and the stock, are supposed to 'free float' the barrel except for the wrap location. If you've ever examined the Finnish M39 or even the re-worked M91 rifles, you'll often find that the barrel doesn't touch the stock except at the nosecap (M39) or at the front band on the M91.
I wrapped a couple of my PU snipers at the front band and used metal shims to mimic this but for some reason the group size increased. Not sure why, but my '43 PU shoots better without the wrap treatment.

I guess...like the guy said...'it depends'...and it does on the rifle set up... I use a very thin wrap, GI issue arm sling bandage that you can almost see thru and I have floated the barrel so it only has support near the barrel / receiver junction. I think (no science involved) that this assists in harmonics due to the thin barrel Mosins have.
If properly wrapped it is still basically floating but with a forward support to deal with harmonics (barrel whip) of the thin barrel. Over wrapping could have a negative effect by creating a pressure point not a support....so during a rounds movement and the vibration that precedes it the wrap would decrease movement by limiting whip....but is not thick enough to 'capture' the barrel in place with the stock.
That is why I requested the pic of the original wrap that would perform as I've described in a properly relieved stock.... no overlap...thin.
Thick barrels are excellent for a total floating platform...thin barrels are often bedded to deal with harmonics...the barrel wrap on the thin Mosin barrel is an in between.
I've done this on my three snipers and all shoot less than 1 moa @ 100 yards.
I know that many or most of you know this but I thought I'd post the comment for those interested.
 

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It's the same sort of principle with the SVD, which has a super model thin barrel compared to most tifles.From what I can gather Russian snipers were taught to primarily support it with a hand cupped under the mag as opposed to around the handguard as that creates pressure on the barrel.I have shot mine both supporting it with a hand around the handguard and supporting it under the mag and there is a definite difference in POA between the two methods, with the hand under the mag support being repeatably consistent.With a hand under the mag it also balances perfectly.
 

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this is a very interesting thread; who would ever thing an Izhevsk PU would create this much of a conversation...Just goes to show you what a single simple sniper rifle can do even in theory. By the way, I always shoot better when its cold preferably (30-50 degrees F). When its hot outside like now, I try to shoot after other people so I can watch what the rounds from their guns are doing for the day. Then I try to accomodate appropriately. Never perfect, but adequate. good thread.
 

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Discussion Starter #70
It's the same sort of principle with the SVD, which has a super model thin barrel compared to most tifles.From what I can gather Russian snipers were taught to primarily support it with a hand cupped under the mag as opposed to around the handguard as that creates pressure on the barrel.I have shot mine both supporting it with a hand around the handguard and supporting it under the mag and there is a definite difference in POA between the two methods, with the hand under the mag support being repeatably consistent.With a hand under the mag it also balances perfectly.
Now, would be interesting to see what adding thick wrap in upfront area of the barrel - at the end of the handguard (inside handguards of course) on SVD, would do - ...just saying... ;)

Now, i'm starting to play with Raupleminze accurizing kit. Picture of my barrel wrap as of right now. Time to hit the range (as soon as fog is out).

Wrap.jpg
 

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I hope this isn't straying too far from topic but here's some photos of one my M39 rifles that has the factory shims between the receiver and stock to free float the barrel. The barrel only touches the stock at at the shiny portion at the nose cap. This example is a VKT from 1942 but my 1944 Sako is exactly the same. This VKT is an excellent shooter.

IMG_8183.JPG
IMG_8185.JPG
IMG_8181.JPG

The upper handguard is also carefully crafted to only touch the barrel at this location:
IMG_8187.JPG
IMG_8186.JPG

Here's the shims. Notice the one shim has "AV3" stamped in it.
IMG_8177.JPG
IMG_8178.JPG
 

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Now, would be interesting to see what adding thick wrap in upfront area of the barrel - at the end of the handguard (inside handguards of course) on SVD, would do - ...just saying... ;)
Because of the way the handguards are mounted I don't think it would make any difference as the barrel doesn't sit in a stock barrel channel.The rear handguard retainer features spring steel arms, one on each side for the end of each handguard to sit on.This effectively allows the handguards to be semi-floating to allow for changes in temperature and keeps the handguard tension more constant.
 

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Discussion Starter #74
Ok, so this is getting really interesting. Without barrel wrap, my rifle didn't care much for SB 174gr HPBT. This PU was clearly favoring PPU Match 182gr. Now that's all cool, but i'm almost out of that ammo and PPU won't have anything back until October (i just talked to them today morning). Anyway, because of this, I was happy to see how rifle would act with barrel wrap, since I have to wait long time for PPU ammo anyway - nothing to lose (normally, i would be very happy with shims i have from Raupleminze accurizing kit - I wouldn't touch anything). So i went ahead with the barrel wrap (picture in post above). Now, POI of course changed, i made quick adjustments and shot this group with SB 174gr:

174gr-Wrap.jpg

Satisfied with what i'm seeing, I added rounds into the mag and I switched immediately to my steel target 512 yds - elevation turret lines up close enough with this load - i knew i will be on plate from previous days shootings. And I got this "miracle" group:

500yds-174gr-Wrap.jpg

Through my spotting scope i could see nice blob - couldn't really tell how close those shots landed to eachother, but I knew it's going to be close...I would never expect to see what i found. Jaw dropped. Here is whole target - you can see how group was moved by wind. I was actually holding on the right side of the triangle.

500yds-wind-shift.jpg

I checked chamber temperature with my tool. It was at 112F (I had morning fog just lift up and air temperature was still only 72F but with almost 100% humidity).
I quickly decided to switch back to 100yds and try to shoot Barnaul 148gr (steel case). And got this:

148gr-Barnaul-Wrap.jpg

At this point I'm happy like a little baby. I'm not saying this is .5MOA gun, but this PU clearly can out shoot me and i believe this is solid sub MOA rifle.
I marked my front and rear screw with the red pen. I will remove them and add blue loctite and call it a day.
Barrel wrap stays!
Few notes - seems to me that rifle groups better when i'm resting it right past the magazine. Barrel temperature (chamber), never exceeded 130F. I'm still learning how to be consistent at the trigger on this rifle. It's not heavy, but I wish it would break more consistently (if this makes sense to you guys). It favors rather decisive trigger finger movement...
 

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Nice shooting Rob... for me that's the fun of the Mosin sniper... experimenting etc. You are correct on the hold point forward of the magazine or on the deep portion of the stock...never on the thin wood section forward of the rear barrel band...you'll create a pressure point.
Isn't that cool how that 'works' with the wrap.
 

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Discussion Starter #76
I hope this isn't straying too far from topic but here's some photos of one my M39 rifles that has the factory shims between the receiver and stock to free float the barrel. The barrel only touches the stock at at the shiny portion at the nose cap. This example is a VKT from 1942 but my 1944 Sako is exactly the same. This VKT is an excellent shooter.

Here's the shims. Notice the one shim has "AV3" stamped in it.
View attachment 3709477
Very cool. Looks like they nailed that shim into the stock! Savages! :)
 

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Discussion Starter #77
Nice shooting Rob... for me that's the fun of the Mosin sniper... experimenting etc. You are correct on the hold point forward of the magazine or on the deep portion of the stock...never on the thin wood section forward of the rear barrel band...you'll create a pressure point.
Isn't that cool how that 'works' with the wrap.
You got that right, but I will tell you, it's the same for all com block guns. You have to put some time in to them to max them out. I believe this is the main reason why so many people are turned off by AKs, SKSs, PSLs and Mosins. They expect to open the box, load some cheap ammo and have .5MOA gun...lol, that's not going to happen.
 

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This has been a great thread! I have been "creeping" on it since the beginning and wanted to see how things played out. It is awesome to see how responsive these rifles are with a little tuning, decent ammo, and patience. Great shooting and thanks for sharing!
 

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At this point I'm happy like a little baby. I'm not saying this is .5MOA gun, but this PU clearly can out shoot me and i believe this is solid sub MOA rifle.
I marked my front and rear screw with the red pen. I will remove them and add blue loctite and call it a day.
Barrel wrap stays!
Few notes - seems to me that rifle groups better when i'm resting it right past the magazine. Barrel temperature (chamber), never exceeded 130F. I'm still learning how to be consistent at the trigger on this rifle. It's not heavy, but I wish it would break more consistently (if this makes sense to you guys). It favors rather decisive trigger finger movement...
Interesting results and testing Rob.

You have any method to how you tighten your action screws as well?
 
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