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  #46  
Old 04-06-2020, 07:20 AM
Mouzetrap

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Quote:
Originally Posted by roberts257ai View Post
Quote:
Originally Posted by PJKEUHLEN View Post
Interesting approach Mouzetrap. The photos help understand the approach a lot. I am getting similar groups at 100yds with my HB BMAG in a Boyds stock using a Limbsaver to adjust barrel harmonics. Will be interesting to see what happens when yours goes into your Boyd's. I am definitely considering following your lead, so I have some followup questions:

I have some questions about your approach.
- Can you provide link or stock number for shims you used?
- What torque value did you use to reset the barrel against the shim?
- How did you apply the torque? (I don't know how I would adapt any of my automotive torque wrenches to do that)
- Did you use a thread locker fluid when reinstalling the barrel? Which/why?
- Did you reinstall barrel set screws? If so, since you had to use an easy out, I assume the old ones were damaged in removal. If you reinstalled set screws, please provide info on what you sourced and any torque values you used.

Thanks for sharing!
Same questions here

Mousetrap, really like where you are going with this <img src="https://www.rimfirecentral.com/forums/images/smilies/sthumb.gif" border="0" alt="" title="Blue Thumb" class="inlineimg" />
Lol well I would hold off on any following for sure as this all may be a fluke, especially if you are getting the same groups, that’s great.

Hey look a there, thanks mods, I have my attachment privileges.
Here are the shims from McMaster. Ideally you would have both surfaces trued on a lathe and a shim that is the right OD and thickness, but I don’t have access to a lathe right now so this was just a quick test. It looks rather hideous, but if it works then I will make a solid shim that is the right OD around barrel but has a recoil lug, then hog out all of the bedding in the stock now and only bed the action and recoil lug.

Torque was by hand/feel using one of those rubber strap oil filter wrenches. No torque value as I didn’t have an ingenious way to do it either lol. Plus I’m not sure it would change much going from 20-40ftlbs on HS. Plus the bullet going down the barrel is actually trying to tighten it more as you shoot it.
No loctite, wanted to protect the threads since it’s SS on SS, worst case for galling, so I used the silver antisieze.

I didn’t install the set screws, only thing holding it on is how it’s threaded in the action.
I haven’t measures the set screws to see what size they are, but you are right I will need to replace one if I need to use them. Hopefully I don’t but if I do, I’m going with black oxide vs SS
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  #47  
Old 04-06-2020, 07:28 AM
Mouzetrap

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Forgot to mention, since my starting value was .087”, I used a .060”, two .010” a .005” and two .001”. Since the .001” are paper thin, I put them in the middle of the stack and left the thicker ones on the outside of the shim stack.

But as I said, y’all hold off and let me validate this thing. Only one of use needs to have a violated action/barrel and two hacked up stocks haha.
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  #48  
Old 04-06-2020, 07:49 AM
Mouzetrap

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And B23, I think we are saying the same thing, but in a different way , all good sir &#x1f44d;&#x1f44d;
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  #49  
Old 04-06-2020, 12:56 PM
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How are you setting your headspace, do you have a set of go/no go 17 WSM HS gauges?
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  #50  
Old 04-06-2020, 01:35 PM
Mouzetrap

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I don’t have go/no-go gauges for this rifle but used fired brass out of this gun and new ammo to set it. Was really close from the factory....002” less shim and new ammo won’t chamber. I am actually .001” less HS than where the factory had it as spent brass has some resistance on chambering and another thou shim will line my marks back up.
Backwoods...yea, why yes I am haha
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  #51  
Old 04-07-2020, 08:36 PM
Mouzetrap

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Well guys not sure what’s up, I’m really confused. I am hoping it’s either a bad scope (vortex) Or I am dealing with too hot of a barrel as I didn’t give it long between these groups.
At first I thought it was cleaning as I started shooting with 45 rounds since cleaning and the barrel shows copper in it but my best ever group with the gun was around 125rounds without cleaning. The very next few groups were awful, like 3-4”. It seems every group starts off where the first shot is low, then high then two or three hit the same POI.
I do know torquing the action to only 15inlbs doesn’t work, that’s where I started and the groups were awful. It seems to like 30 the best but the problem is I have to keep retorquing after ever group. The bolts aren’t backing out as I marked them, must be the wood compressing.
I even tried wedging the barrel between the stock too, that moved POI but didn’t help groups. Tried shooting with rifle supported near mag box and not off bipod, no changes.
I did notice at the end that some of my ammo has varying OAL which will change everything and mess up groups as it does with my CF stuff.

Like I said, got two decent groups with a hot barrel and high round count, then most everything else is bad. This is 5 shots for both groups.
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  #52  
Old 04-07-2020, 08:39 PM
Mouzetrap

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As an example, the first group shot on here was the good one, the others just fall apart even after some time to cool the barrel a little...but barrel was warm when I shot good group.
Low shots are always the first shots.
Which I had my chrony with me.
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  #53  
Old 04-07-2020, 08:40 PM
Mouzetrap

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I may just rip this fun apart and redo everything, or use it as a tomato stake. Problem is I have 1,000rds if this ammo.
I may try sorting by OAL just for grins.
Guess I will clean the barrel too and try that, although the good group was with high round count as mentioned.
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  #54  
Old 04-07-2020, 08:46 PM
Mouzetrap

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Sorry for all the posts but it does weird things when I type forever and attach multiple pics to one thread.
Here is another group sheet, all shots are at least 5, some six. I get a few two bullets going into one hole then it loses its mind.
Did this same thing with the other stock but I thought it was the stock touching.
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  #55  
Old 04-08-2020, 03:30 AM
Old Hickory

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What the heck!
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  #56  
Old 04-08-2020, 05:33 AM
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Had similar results yesterday.
So I never new about the set screws on the barrel so I tighten them. My 3 shot groups tightened up but still had a 1 shot flyer, about 1 inch. After 4 groups, everything fell apart. All groups were 6 inch. Rechecked everything with no results.
Switched to 25gr and groups tightened up to around 3 inch.

Itís either ammo or barrel heat.......
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  #57  
Old 04-08-2020, 06:26 AM
jaia
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Welcome to the world of Winchester rimfire ammunition.
They make varminting/hunting/plinking ammo, not precision target cartridges.
Look at the 17wsm cartridges closely and use a ballistic chronograph when testing.
Variations in bullet seating depth/angle, brass dimensions aren't consistent,
plastic tips bent/broken/malformed and mv spread will explain y'er results.
For turning rodents into meat spray it'll do the job, just don't expect match grade cartridges.
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  #58  
Old 04-08-2020, 08:46 AM
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Mouze, when you swapped stocks, did you remember to remove the escutcheons from the factory stock and put them in the new stock?

If you didn't, it would help explain why the action screws aren't staying consistent.
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  #59  
Old 04-08-2020, 08:58 AM
Mouzetrap

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Thanks for the responses guys.
Sorry about your results Robert! I hope it’s barrel heat and plan to test this next time out.

I agree the ammo is awful so I plan to try to sort/group based off of what I can measure..but I have too many good groups to say it’s all ammo quality related.

Good suggestion B23 but yes I did reinstall them in the Boyd’s.

I am using a Vortex Crossfire II and have seen a lot of quality issues with these as they are made in China...so I am speaking with Vortex now as the POI would shift during the shooting session with no explanation. I have a couple other of their scopes and they are as good of quality as my NF scope...but aren’t made in China.

I also just ordered a one piece scope base as suggested earlier.
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  #60  
Old 04-08-2020, 09:01 AM
Mouzetrap

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Since I have plenty of bedding material, I may rebed it with nothing under the barrel and using the washers as a recoil lug.
Another thing could be if I am running 0.001” less HS, this could make the variance in ammo OAL more sensitive as I’m closer to the lands.
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