Elwood Posted November 13, 2009 Report Share Posted November 13, 2009 When is loose to loose? When the primer falls out? When you can seat a primer with your fingers? When you feel bugger all resistance using a primer seater? Link to comment Share on other sites More sharing options...
Oly Posted November 13, 2009 Report Share Posted November 13, 2009 Yes to all of the above! Are you able to measure the internal diameter and see how much it has changed? Link to comment Share on other sites More sharing options...
Laurie Posted November 13, 2009 Report Share Posted November 13, 2009 When is loose to loose? When the primer falls out? Yes, rather past the point of being too loose I'd say! When you can seat a primer with your fingers? Ditto to above question When you feel bugger all resistance using a primer seater? Personally, I wouldn't carry on using the case at that point, but remember the leverage in the press or priming tool. Sometimes, seating that apparently requires damn all effort still sees the primer held fairly securely in the pocket. It's often a matter of noting that that batch of cases is getting near the end of their life and need scrapping after that loading / firing More generally, you need to think about what loose or 'looseish' primers are telling you and relate the condition to your loads. if it's a mild load, a primer that seats easily (but doesn't fall out or anything silly like that) will still seal the flash-hole / rear end of the case efficiently, which is what it's all about. BUT .......... if you're loading hot, you risk gas leakage from around the primer. I think safety is rarely a real issue here (as opposed to a disastrous overload that massively expands the pocket and blows the primer letting a lot of gas escape), rather looking after your bolt. Looseish primers that let a little bit of gas out will erode the bolt face if it happens often enough. The other thing about loose primers is relating the condition to your loads, case make and case history. If it's a fairly hot cartridge and you're using full-power loads, the primer pocket will often be the thing that wears out first so to speak, each firing expanding the case head just a little until the pocket is oversize. You can sometimes carry on by changing the primer make as their diameters vary slightly. I've found Remington 9.5 primers sometimes seat over-easily in brand new brass for instance while other makes take a lot of pressure to seat them in the same cases. If your cases are knackered here after only a couple of loadings, you either need to drop the charge or change make of case to a tougher variety. (Lapua might be bloody expensive but they're really tough at the back - if you get expanded pockets with this make in a few firings, it usually means you're running too hot!) Sometimes you get one or more cases in the box noticeably looser than the rest, which may be that they've just happened to always get the highest pressure loads bearing in mind that you can get quite a large range of pressures from a single load. On the other hand, you do get the occasional rogue case with a soft case-head, or even a whole batch of cases that see the primers go loose very quickly. In this situation, your loads are 'too hot', not in absolute terms maybe, but for that batch of cases. I used to find this with Federal brass some years back - don't know if it still applies today - once-fired brass from factory loads seeing primers needing hardly any pressures to be seated in maybe half the cases. Some (rich) people in the target shooting world seem to be happy to live with case-life of only two or three firings before they get loose pockets when they scrap the case. To me, that says they're really close to the safe pressure limit, and are open to some little change or combination of changes putting them over the top with the risk of blown primers or wosre. Laurie Link to comment Share on other sites More sharing options...
TonyH Posted November 13, 2009 Report Share Posted November 13, 2009 More generally, you need to think about what loose or 'looseish' primers are telling you and relate the condition to your loads................[snip].............Some (rich) people in the target shooting world seem to be happy to live with case-life of only two or three firings before they get loose pockets when they scrap the case. To me, that says they're really close to the safe pressure limit, and are open to some little change or combination of changes putting them over the top with the risk of blown primers or wosre. Laurie This is an excellent primer (!) on the subject, thanks very much. I've read lots in the past, but this is a usefully succinct overview of primer pockets... I've only rarely dumped a case because I thought its pocket was too loose, but in 22-250 especially I think one has to keep an eye on things. Only yesterday, I was running some brand new WW brass through my (also new) 22-250; when assembling the loads, I was a bit surprised by the variation in "feel" during priming with my Lee auto hand-held job (had it for years, know it backwards). This was with fully prep'd cases, sorted for weight, uniform within around 1%, all primer pockets uniformed with the RCBS tool. Is this unusual? Regards, TonyH Link to comment Share on other sites More sharing options...
Laurie Posted November 13, 2009 Report Share Posted November 13, 2009 Only yesterday, I was running some brand new WW brass through my (also new) 22-250; when assembling the loads, I was a bit surprised by the variation in "feel" during priming with my Lee auto hand-held job (had it for years, know it backwards). This was with fully prep'd cases, sorted for weight, uniform within around 1%, all primer pockets uniformed with the RCBS tool. Is this unusual?Regards, TonyH No, not unusual Tony in my experience. I think it's just tolerances in the primer pocket and primer cup dimensions - you get a slightly large pocket plus a slightly small cup and the Lee AutoPrime is sensitive enough for you to feel it. Like I said in my previous post, it sometimes helps to change the make of primer if you get too many feeeling a bit on the loose side with new cases. I often used the Russian manufactured PMC large rifle primers when this happened as they seem to be toleranced on the big side, and they are very good primers too as well as being amongst the cheapest on the market. Sadly, when PMC folded, York Guns couldn't get any more. They're still available in the USA under the 'Wolf' brand name, and highly regarded over there, but I've never heard of them here - if anybody has, will they shout please? Laurie PSD mewntioning PMC primers. While the large rifle version is excellent with tough cups too, beware of the small rifle with bright copper coloured cups that are still to be found in some dealerships - they're very 'soft', great for light loads or low pressure cartridges like .22 Hornet, but they crater and pierce with normal loads in .223, 6BR, the PPCs etc. Link to comment Share on other sites More sharing options...
skany Posted November 13, 2009 Report Share Posted November 13, 2009 ALL my 243 ai brass has lose primers now! some are real bad! as a test i mixed some real bad ones in with the best & they all still shot the same @ 200yds altho if the 243 lapua brass wasent so expensive id proberly replace it anyhows! cheers Andy Link to comment Share on other sites More sharing options...
17 Rem Posted November 16, 2009 Report Share Posted November 16, 2009 skany, how many reloads did you get from your cases before you noticed the primer pockets becoming slack? Link to comment Share on other sites More sharing options...
Andrew Posted November 16, 2009 Report Share Posted November 16, 2009 skany,how many reloads did you get from your cases before you noticed the primer pockets becoming slack? That depends on how how hot you load them. High pressures will do it in a single loading.~Andrew Link to comment Share on other sites More sharing options...
foxing2night Posted November 17, 2009 Report Share Posted November 17, 2009 Laurie, Very informative post as usual Primer pockets are an issu that a lot of people do not understand,,, Good post and good read!!!!! Darrel Link to comment Share on other sites More sharing options...
skany Posted November 17, 2009 Report Share Posted November 17, 2009 skany,how many reloads did you get from your cases before you noticed the primer pockets becoming slack? Hi two that was with a load that was under max for 243! ive backed it back two full grains & still get almost the same velocity! Andy Link to comment Share on other sites More sharing options...
Ronin Posted November 17, 2009 Report Share Posted November 17, 2009 Every time I reload and reprime, there is the odd one (or two) pocket that feel loose, I make mental note to bin case after firing - of course I wouldnt want to waste the .0001p primer ive just put in would I Then I make mental note to mark case with felt pen to show it should be scrapped --but never do. Maybe next time I re-load, I will recall this thread Link to comment Share on other sites More sharing options...
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