fieldwanderer Posted July 9, 2014 Report Share Posted July 9, 2014 I'm having alsorts of trouble figuring this one out so hoped I could draw on your knowledge and experience please Rifle's a sako 75 in .22-250, it's been re-barrelled by someone who came very highly recommended but, as far as I know, the action wasn't altered at all. I've been using ppu brass in the rifle, with 65gr sierra gameking bullets (1 in 10 twist) and superformance. getting ~3600fps in winter and ~3750fps in summer. It's a hot load but no pressure signs other than the bolt click but it's not a pressure sign as such (i don't think). I tried some remington brass too but can't remember if the click was there or not. I've been using lee dies but have some rcbs competition dies on the way and some lapua brass I recently switched to 69gr matchkings, just out of curiosity, but decided to tone things down and find an accurate load that's more pleasant to shoot, I went with data from one of the powder manufacturers online (for superformance obviously) and started midway (sorry, can't remember the figures). Again, no other "signs" but the click was still there. I dropped a grain and a half and tried again - same story, even 0.6gr above minimum. So, I decided to try a different powder. A trip to the toy shop later and a shocking amount of £'s lighter, I had some viht n550 which I knew I could find data for. IIrc, start load is 30.6 and max 34.6. so, I started at 32gn reasoning that it's a little used action and a fairly new barrel. The first shot, the bolt opened very nicely and I thought for a moment I'd finally sussed the problem - again no pressure signs at all. The other 9 weren't so good though but I shot a 2" group at 250yds with no load development at all. Since then, I've done some investigating and found; the click is still there but much less force required with an empty chamber as above with a f.l. resized empty case click is very heavy with a fired case (no matter what load was used in it) as with opening bolt having just fired - sometimes requires a gentle to firm tap with my palm no click at all with bolt stripped and just the bare bolt put into rifle (i.e. no firing pin, spring, spacer or rear shroud) Any ideas what's going on? Quote Link to comment Share on other sites More sharing options...
Underdog Posted July 9, 2014 Report Share Posted July 9, 2014 May just be the extractor slot in the barrel mate. The extractor is clicking off the barrel onto the brass. The barrel slot should taper to nothing. If not it can cause a click. Is it clicking as the bolt first starys traveling back? Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 9, 2014 Author Report Share Posted July 9, 2014 (edited) Ah, sorry missed a bit of detail there: it's as the handle's turned, the firing pin cocks fine but then the you hit a fair bit of resistance to turn it the last bit before the bolt can be pulled back I'd say it's the primary extraction except the click is there even with an unfired case or an empty chamber (albeit to a lesser extent than if a fired case is in the chamber) Edited July 9, 2014 by fieldwanderer Quote Link to comment Share on other sites More sharing options...
Underdog Posted July 10, 2014 Report Share Posted July 10, 2014 How about blacking the bolt with an oil lamp and look for high spots. May be the new barrel is set a few thou to deep! Quote Link to comment Share on other sites More sharing options...
activeviii Posted July 10, 2014 Report Share Posted July 10, 2014 Strip your bolt and check for burrs and floating carp. Clean, polish and a very light oil. Dry lube if you can. Polish the back of the bolt lugs and use a good grease. But tiny amount. Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 10, 2014 Report Share Posted July 10, 2014 Well, I can't help out what the problem is, but ! I have recently had the same problem, never had it before in nearly 8 years. Reloading is all identical, the only difference i have made is using lapua brass, but it dooes it with those, and with nosler. I will be stripping the bolt, and extractor this weekend and after tests if the problem is still present I will load some virgin brass, with a drop in charge just to seem it goes. Quote Link to comment Share on other sites More sharing options...
kent Posted July 10, 2014 Report Share Posted July 10, 2014 This is not something that's easy to describe on the net or diagnose, I should get it back to whoever did the barrel job. If I took a wild punt it might be wildly unfair to the smith. I know this sounds condescending but honestly some UK calling themselves smiths and getting praise for producing what amounts to pretty guns and are pretty poor engineers of very little training, so if you don't get a satisfactory answer go elsewhere and remember everyone makes mistakes Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 10, 2014 Report Share Posted July 10, 2014 Ìf the problem is anything like mine, which it sound extremely similar then i am almost certain its not a Smith issue. My first thought is the extractor catching, as its only stiff or as has been commented feels like a click, or an obstacle that an upward knock will enable the bolt to full lift. Firstly it will be checked for debris, then checked with an offending round, i will then remove the exctractor and check,then try with firing pin removed, and check, if it is still catching then I will try different case's, check, reduced loads, check. If all else fails then : : : : : I'll let you know the outcome. Oh! That will be a Saturday morning job. So you'll have to wait. ;-) Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 11, 2014 Author Report Share Posted July 11, 2014 (edited) Having done a little lathe work myself and spoken at length with the guy who did the work, I'm confident it's not down to him - though I'm happy to keep an open mind. Here's another question then; With bolt in the receiver, firing pin cocked, empty chamber, safety off. Is it normal to feel a click at the top of turning the bolt; I.e. More force required to overcome something before the bolt is fully turned and ready to be pulled back? Mine does With firing pin, spring, rear part removed from the bolt and everything else as in last example, it doesn't As in the second example, bolt stripped, in receiver, safety off but with an empty, fired ppu case in chamber it has the heavy "click" As in the last example but with empty, fired remington case. It has slight click (just like the first example). A used, f.l. Resized ppu empty does same as remington above. Yesterday, I stripped the bolt, thoroughly cleaned it and the rifle, polished all the "ramps" on the bolt (those on locking lugs, firing pin cam and primary extraction) and coated them with smoothkote. That'll've cured when I get home tomorrow so I'll see what happens then but I'm not holding my breath. Edited July 11, 2014 by fieldwanderer Quote Link to comment Share on other sites More sharing options...
Underdog Posted July 11, 2014 Report Share Posted July 11, 2014 Please black the lug end of the bolt and check the barrel is not rubbing on the bolt face. If the head space is minimal it could be the 'crammed' brass pinging from the chamber. Maybe try with a lubed case !! Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 11, 2014 Author Report Share Posted July 11, 2014 Sorry u.d, I tried that when it was mentioned the other day - ink stayed intact but I'll try again later just to be sure. What would a lubed case show? Quote Link to comment Share on other sites More sharing options...
Underdog Posted July 11, 2014 Report Share Posted July 11, 2014 If the head spacing is tight the bolt may be pushing the case in the chamber so hard causing it to stick in there and the click is it letting go on primary extraction. Lubrication should lesson the grip of the case and thus the click may stop just for us to pin point the problem.....if it is that etc. Just trying to eliminate things to aid diagnosis matey. Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 11, 2014 Author Report Share Posted July 11, 2014 News Underdog; I wasn't questioning your way of thinking - I just like to understand things, as it happens though I forgot to try lubing the case. However, the click is still there with no case in the chamber but not enough to cause an issue; it's not noticable when the firing pin needs to be cocked I believe that's because of the "effort" already required. I've come to the conclusion it's not a problem with the correct brass (i.e. NOT ppu), though my lapua brass and new dies still haven't arrived. polishing things may have helped a tiny amount, I'm not sure. I think, if someone with the same rifle (or who knows the 75 well enough) were to say it's normal to feel a fairly distinct "click" just after the firing pin is cocked, I'd be happy to put it down to just the ppu brass being a bit out of spec for my rifle. I'm struggling a bit with explaining this though, short of doing my first ever youtube vid, I'm running out of ways to put it into words As a side note, the smoothkote was a waste of time - it just rubbed straight off! Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 11, 2014 Report Share Posted July 11, 2014 It happened to me at Diggle whilst shooting Mcqueens. There's tension on the the bolt anyway as I only FL after so many loads, but a definite stop on lifting the bolt, needing a decent knock to fully open the bolt. ? Quote Link to comment Share on other sites More sharing options...
kent Posted July 11, 2014 Report Share Posted July 11, 2014 News Underdog; I wasn't questioning your way of thinking - I just like to understand things, as it happens though I forgot to try lubing the case. However, the click is still there with no case in the chamber but not enough to cause an issue; it's not noticable when the firing pin needs to be cocked I believe that's because of the "effort" already required. I've come to the conclusion it's not a problem with the correct brass (i.e. NOT ppu), though my lapua brass and new dies still haven't arrived. polishing things may have helped a tiny amount, I'm not sure. I think, if someone with the same rifle (or who knows the 75 well enough) were to say it's normal to feel a fairly distinct "click" just after the firing pin is cocked, I'd be happy to put it down to just the ppu brass being a bit out of spec for my rifle. I'm struggling a bit with explaining this though, short of doing my first ever youtube vid, I'm running out of ways to put it into words As a side note, the smoothkote was a waste of time - it just rubbed straight off! Don't shoot with any lube in your chamber, you can ruin the chamber as it acts hydraulically against the wall. It also raises pressure. Same with wet ammo and wet chambers Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 11, 2014 Author Report Share Posted July 11, 2014 It happened to me at Diggle whilst shooting Mcqueens. There's tension on the the bolt anyway as I only FL after so many loads, but a definite stop on lifting the bolt, needing a decent knock to fully open the bolt. ? Only needs a smack with fired ppu brass (that's not been resized at all), If you open your bolt, close it on an empty chamber and lift the handle, does it have a stiffer spot near the top that clicks a bit as you push past it? to put into perspective, this can be done with the index finger out straight but is a little bit stiff (must be about the same as the effort it takes to cock the firing pin). Don't shoot with any lube in your chamber, you can ruin the chamber as it acts hydraulically against the wall. It also raises pressure. Same with wet ammo and wet chambers Thanks Kent, knew not to but always worth mentioning in case Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 11, 2014 Report Share Posted July 11, 2014 http://youtu.be/xynylpg0QtQ Quote Link to comment Share on other sites More sharing options...
Underdog Posted July 11, 2014 Report Share Posted July 11, 2014 Hmmm, does it do it with the trigger pulled and lifting the bolt? Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 11, 2014 Author Report Share Posted July 11, 2014 (edited) That's it dougy, just the same! Especially clear the last time you lift the bolt. Is it meant to be like that? With the fired ppu brass, mine needs a whack to pop it past that last bit but with the few remington cases I have, it's more or less the same as an empty chamber. With the firing pin "fired" it's difficult to tell as the resistance is all the way through the upward stroke. Edited July 11, 2014 by fieldwanderer Quote Link to comment Share on other sites More sharing options...
Dougy Posted July 11, 2014 Report Share Posted July 11, 2014 Hmmm, does it do it with the trigger pulled and lifting the bolt? at the same time As in pressure still on the trigger whilst lifting the bolt Put all gear away now, and popping out for some amber nectar. Will spend some time shooting and looking at fieldwander issues tomorrow. Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 12, 2014 Author Report Share Posted July 12, 2014 Thanks again dougy (and everyone else) for the help, I'm not sure there's an issue now (other than brass). It would be nice not to have the click but if it's normal, I'm not too worried. I'll know more when (if) my new brass ever turns up. Quote Link to comment Share on other sites More sharing options...
kent Posted July 12, 2014 Report Share Posted July 12, 2014 Still if you have already spoken to your smith I should approach another for an opinion (without saying too much to lead them on), too hard to diagnose without a look see. If it was something I had worked on i should want it back to look at even if I was positive it wasn't my fault Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 12, 2014 Author Report Share Posted July 12, 2014 Kent; in all honesty, I've a feeling what I thought was a "problem" is actually normal.... With the privi brass, no it's not normal - one should never have to hit or force a bolt BUT, the slight click with an empty chamber or remington (and, I suspect, other manufacturers) brass - looks to be normal. I will, however, ask the local RFD when I go next (likely tomorrow ) as I know he and his sons use nothing but sako's and it'd put my mind at rest. Obviously, if they say differently I'll be speaking to the gunsmith in question Quote Link to comment Share on other sites More sharing options...
kent Posted July 13, 2014 Report Share Posted July 13, 2014 Kent; in all honesty, I've a feeling what I thought was a "problem" is actually normal.... With the privi brass, no it's not normal - one should never have to hit or force a bolt BUT, the slight click with an empty chamber or remington (and, I suspect, other manufacturers) brass - looks to be normal. I will, however, ask the local RFD when I go next (likely tomorrow ) as I know he and his sons use nothing but sako's and it'd put my mind at rest. Obviously, if they say differently I'll be speaking to the gunsmith in question I have shot a 75 for well over a decade and mine don't do it that I have ever noticed at least over a heck of a lot of rounds Quote Link to comment Share on other sites More sharing options...
fieldwanderer Posted July 13, 2014 Author Report Share Posted July 13, 2014 Oh!? thought I'd figured it out Soo, just to check; with the firing pin already cocked, and the bolt closed on an empty chamber but in all other ways "ready to fire", your bolt lifts perfectly smooth all the way to up as far as it'll turn (where it needs to be before it can be pulled back)? Quote Link to comment Share on other sites More sharing options...
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