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Post by honestjohn on Sept 30, 2022 11:39:23 GMT
Some of you may remember that I have a problem with my favourite BB gun, my H&K USP. My problem is to do with the hammer strike not landing accurately on the release valve. I need to further investigate this as it seems to be related to the pivoting bit the actual hammer strikes not being in exactly the right place. Before I could pursue my investigations further, I’ve buggered the long narrow spring that fits down the side of the blowback unit, when it got displaced when I was racking the slide! I have been totally unable to source a new one on the tinterweb, and spares for this pistol seem very hard to come by. I measured the damaged spring and it seems to be wound from 0.23mm wire and has an ID of 1mm and an OD of about 1.87mm. I have sourced some 0.23 music wire and when it arrives I’m going to have a go at winding a spring. I’m thinking of using a 1mm drill bit as a mandrel, but as I’ve no experience of doing this, I’m thinking that a 1mm mandrel will produce a bigger than 1 mm internal diameter when it relaxes? If anyone has any experience of winding tiny springs (or where I can buy an original) I’d love to hear your advice.
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Post by honestjohn on Sept 30, 2022 15:04:12 GMT
Update. Just sent for some 1mm stainless rods. I was thinking that these would be stronger for a mandrel without the helix’s cut into a drill bit. May be some weeks before I can try this out as I’m due to go to Devon soon for about a month. I’m keen to solve this issue, so that I can get back to seeing what the hell is wrong with the firing mechanism. This buggered spring is just a sort of collateral damage issue caused by me, but can’t really progress without I solve it.
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Post by HeadHunter on Sept 30, 2022 16:22:33 GMT
Hi John, in the standard engineering tool books they give a formula for working out the internal diameter of a spring versus the external diameter of the mandrel, unfortunately I can't remember the exact equation off the top of my head but I would 'guesstimate' a mandrel of about 0.8mm would probably be better suited to getting a 1mm internal finnished diameter. I hope that helps John  |
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Post by c220w205 on Sept 30, 2022 16:30:37 GMT
Hi HJ, I have no information for you with regard to your spring dilemma but was intrigued to read that would be coming to Devon soon, may I suggest you take a trip to: Crack Shot if you are anywhere near the Heathfield Industrial Est just off of the A38 at Newton Abbot. It is a well-stocked RFD that has an indoor range as well  |
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Post by honestjohn on Sept 30, 2022 16:54:31 GMT
I’ve had 2 trips already totalling about 3 weeks, and on my first trip I took my target pistol down with the intention of visiting Crachshot to use their 10m range, as I didn’t want to go weeks and months without practice. Didn’t get round to it though as it’s a bit of @ pain to get to, either Dartmouth and over the car ferry, or miles round to get to Torbay! We’re on the coast south of Kingsbridge. Might have another go when I go down next week. Thanks for mentioning it though👍
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Post by honestjohn on Sept 30, 2022 17:24:24 GMT
Shawn, I had a thought that that might be the case, but I’m navigating unknown waters. I’ve found and ordered some 0.7 and 0.8mm stainless, and I’m looking forward to having a go at this project. I’ve got a plan forming in my mind of doing this by hand on my small engineering lathe with the mandrel in the three jaw and supported in the tailstock by a manufactured fixture. I’m thinking of winding towards the three jaw in the headstock maybe 6 mm at a time, then pull another 6mm out of the Chuck and rinse and repeat so to speak. I need to work out the details a bit yet, but I’m thinking that this might only be possible close up to the Chuck with little overhang, due to the fine wire nature of the mandrel. Watch this space!
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Post by c220w205 on Sept 30, 2022 19:48:34 GMT
I’ve had 2 trips already totalling about 3 weeks, and on my first trip I took my target pistol down with the intention of visiting Crachshot to use their 10m range, as I didn’t want to go weeks and months without practice. Didn’t get round to it though as it’s a bit of @ pain to get to, either Dartmouth and over the car ferry, or miles round to get to Torbay! We’re on the coast south of Kingsbridge. Might have another go when I go down next week. Thanks for mentioning it though👍 There is another range down at Ivybridge that I've heard about just off the A38 again but towards Plymouth way. |
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Post by honestjohn on Sept 30, 2022 20:58:12 GMT
I’ve had 2 trips already totalling about 3 weeks, and on my first trip I took my target pistol down with the intention of visiting Crachshot to use their 10m range, as I didn’t want to go weeks and months without practice. Didn’t get round to it though as it’s a bit of @ pain to get to, either Dartmouth and over the car ferry, or miles round to get to Torbay! We’re on the coast south of Kingsbridge. Might have another go when I go down next week. Thanks for mentioning it though👍 There is another range down at Ivybridge that I've heard about just off the A38 again but towards Plymouth way. There is another range down at Ivybridge that I've heard about just off the A38 again but towards Plymouth way. well that’s interesting, Ivybridge might be easier to access. From what I remember Crackshots range fees seemed expensive for an hour, but to be fair that might be just me being tight. My club fees are a fraction of theirs, but then my club is a not for profit type arrangement. |
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Post by c220w205 on Sept 30, 2022 21:15:38 GMT
There is another range down at Ivybridge that I've heard about just off the A38 again but towards Plymouth way. There is another range down at Ivybridge that I've heard about just off the A38 again but towards Plymouth way. well that’s interesting, Ivybridge might be easier to access. From what I remember Crackshots range fees seemed expensive for an hour, but to be fair that might be just me being tight. My club fees are a fraction of theirs, but then my club is a not for profit type arrangement. Here’s a link to the Ivybridge place: The Gun Room |
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Post by honestjohn on Oct 1, 2022 8:01:19 GMT
Thanks for that Buddy. The Gun Room looks really good. Must remember to leave my cards behind! They don’t appear to have a dedicated 10m pistol range set up, but the indoor 20m range looks to have retractable target holders so it looks like they could be set to 10m. worth an hour a week to keep my eye in whilst I’m away. Thanks for the heads up.
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