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Crosman hollow probe build

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Pauly5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pauly5 Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2023 at 9:06am
I did try 15.89 grn pellets too, but the heavier pellets seem to hit a sweeter spot.

15.89 grn
12 pumps = 18.10 / 716
8 Pumps  = 14.86 / 649
4 pumps  =  9.46 / 516

What I really like is that this is a really good plinker too. A couple of pumps will give you enough power for quiet plinking.
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kruzaroad View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2023 at 9:26am
That's interesting I got 652fps average over 10shots which is 15fpe
with hades 15.89gr out of box when first got 362.@8 pumps.
Page 14 of you got to be out there to see,has all 10 chrono numbers.

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J-S View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote J-S Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2023 at 2:45pm
Looking like a good project! 4 pumps for 9fpe is nice power!
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RangerPete View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RangerPete Quote  Post ReplyReply Direct Link To This Post Posted: 25 May 2023 at 9:10pm
Hi Paul,
Have u noticed and skirt “reformation” with your beveled probe?
Makes me wonder if it might be worth making a dedicated “pellet skirt reformer press”?!?!
Something like a small press that holds the damaged pellet by the waist, and a beveled rod is carefully pressed into the skirt to re form it back to round. 🤔
Walk quietly, but carry a big stick.
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Pauly5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pauly5 Quote  Post ReplyReply Direct Link To This Post Posted: 25 May 2023 at 9:46pm
Hi Pete,

I did do some trials to see what sort of engagement was made on a good pellet, and I don't think that there is enough resistance from the barrel for the probe to push the pellet against. So while it won't straighten out a deformed skirt, it does look like it kind of seals inside the skirt.

But it would be possible to make  something that you drop the pellet into and push a probe into the rear of the pellet. I'm sure someone has tried it.
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RangerPete View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote RangerPete Quote  Post ReplyReply Direct Link To This Post Posted: 25 May 2023 at 10:06pm
Ja, what you say about the barrel not offering enough resistance to “grip” the pellet while the probe reforms a damaged skirt, makes perfect sence.

I wonder if u can buy a mini press that would reform the skirt and at the same time swage a pellet.
Maybe the ultra competitive competition guys have already come up with one to make sure every pellet is perfectly uniformly shaped and sized…
Like powder burners who work out individual case volumes and weigh every case for uniformity, I’m sure a pellet swager/skirt uniformer would greatly increase the accuracy of any air gun.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2023 at 8:24am
It's called eyes and a vernier+, scales, or sorting your pellets.

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Pauly5 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pauly5 Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2023 at 9:01am
I guess sorting first, visually and weighing would be the first step, then deal with the damaged skirt ones, or use them for practice.

I have a brass pellet sizer that I used to use when shooting FT, but I don't think i'm good enough for it to make a difference anyway. I have also washed pellets in the past, applying a couple drops of lubricant to a tins worth.

To be honest, I never spent enough time at a bench validating if there was ever any benefit. Now I just check for bent skirts before loading. If I was target shooting I would pre-sort and weigh.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jwabfrog Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2023 at 10:11am
Tinbum sells pellet sizers - obviously only good for reducing pellet size. Link below

https://www.airrifletuning.com/store/tbt-22-pellet-sizer/

I've also been interested in using lubricant but have never actually tried this - Napier sells prelubricated pellets which I think I might try as well as pellet lube:
https://www.napieruk.com/products/power-pellets-22-target-tin-of-500-pellets
https://www.trademe.co.nz/a/marketplace/sports/hunting-shooting/air-guns-parts/ammunition/listing/4147949924
https://www.napieruk.com/products/power-pellet-lube-10ml

Lots of videos on youtube covering pellet cleaning and lubricating:
https://www.youtube.com/watch?v=n9lNFKD3Q-0
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kruzaroad View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote kruzaroad Quote  Post ReplyReply Direct Link To This Post Posted: 26 May 2023 at 10:36am
Head sizing and weighing reduces Flyers. I have no dought on that from target shooting on farm.
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