MikeJ

I'm trimming after resizing........ I really don't understand why there was a suggestion to trim before resizing 😕

Well, I have just sent off 100 cases to Mark. We shall see. Meanwhile I'm looking at a Caselife annealer item (£179) or a Reloader Brass annealer (£220), the latter having a 6 week lead time.

I shall look into it Sir! I'm sitting here looking at eighty cleaned, resized (ha ha) and trimmed cases and was thinking about cracking on and reloading them but will put them to one side for the moment while I investigate annealing services.

Gents, thank you all very much for the helpful pointers, all of which have been taken on board! I'm in no position to get involved in any complex annealing process or have a machine to do it for me, but I will keep a more careful eye on number of firings of each batch of brass from now on. Nonetheless, although I'm probably never going to score successive V-bulls at 1000 yards at Bisley, the shots are close enough for me on the rare occasions that I get the chance to shoot at that distance. Clearly some room for improvement though!

Thanks Popsbengo, The data may have been misleading - sorry. I should have mentioned that a fully-fireformed case comes out at 1.5585" and I was bumping back (or hoping to) 1.5570". Going back to 1.5565" might be more sensible. In my example I had quite a number of cases that were at 1.5575" after firing so used them initially. I think you, and others, in suggesting that either the expander or overly-springy brass (or both) might be correct in where the problem lies. I shall take all that on board and my next reloads will now be with new Hornady and Starline brass and I'll keep a careful eye on how they turn out after resizing. Too many variables with the old brass I think, as those cases had not all been shot the same number of times. Thanks you all for your thoughts on the matter.

Hi Catch-22, No, I'm not removing the ejector, and I'm trimming after f/l sizing. Not that there's much, if anything, to take off, but I'll trim first then size and see how that goes. As I mentioned above, it just seems to be an issue with the 6.5CM brass - perhaps I'm expecting too much from it! Now, there's a thought about the expander......... something else to try! Thanks!

Thanks Pat - maybe it is a lack of annealing. It's something that I've never done, but I'll try keeping the pressure on for a while longer and see if that helps. I think that the lube is consistent. It's not a problem that I've had with .308 and .223 cases, so perhaps the 6.5CM brass is a little more sensitive to multiple firings and lack of annealing.

Laugh at me if you will, but I use Lee dies for all my reloading activities (.38/.357, .223, .308, 6.5, 7.92) and am pleased with the outcomes. However, over the past year I have been using the Hornady "Headspace Comparator Kit" as a means of adjusting the dies to give the cases a modest set back ("bump"?) rather than a full-on re-size in anticipation of the brass lasting a little longer - particularly for the 6.5CM. However, taking a practical example of a number of Hornady cases, all fired several times and fresh out of the chamber at (using comparator insert 'C') 1.5575" I set the f/l die to size a case to 1.5570". When the case is chambered the bolt (with firing pin removed) drops quite happily under its own weight. I then run the remainder of the cases through the die only to find that some are bumped back to 1.555" and some have "grown" to 1.5585" and are thus stiff to chamber. Am I doing something so obviously wrong that I should never, ever be allowed near a reloading bench, or is it that the Lee f/l die is just unsuitable for this kind of thing?

A shooting acquaintance mentioned that a carbon ring can also cause high pressure...…. I wouldn't have the faintest idea whether I have a "carbon ring" 😰 or not...…… would it look anything like this? I have scrubbed with "Carb Out" and it remains in place so I'm not convinced!

Thanks both! N160 is on the list - I'll be trying it out soon!

Thanks David. A while ago I weighed my once-fired brass with the following results: Peterson 175gr, Sellier & Bellot 165gr and Hornady 155gr each having water capacities of 3.35cc, 3.38cc and 3.45cc respectively. Your conclusion that the Peterson brass is thick-walled thus seems sound. The primer pockets are still tight in the Peterson cases which had the lower powder charge. On the matter of my COAL of 2.825" for the 42.5gr RS62 loads, I have measured a round with the bullet set against the rifling and that gives a COAL of 2.910", so from this I would assume (perhaps wrongly - always happy to be educated, please!) that there would have been a good 75 thou' jump to the lands. Perhaps the difference in case capacity between, say, the Peterson and Hornady brass, of 0.1cc is enough to cause 42.5gr RS62 to go over pressure (although I used a long drop tube and there was no "crunching" when I seated the bullet. I'll give N160 a try (I had been thinking N150 but will take your advice).

DaveT - thanks very much for your observations. Cases were 2x fired (not 1xF as I mentioned at the beginning). As for the nodes, I have checked my notes and found the two loads mentioned at the start were those which gave me 1/2" groups of five shots at 100 yards so I stuck with them. I'll start again and work through to see whether anything has changed. As for COAL, I took the 2.825" to be the "official" maximum length, which with the Scenars I doubt would be jammed into the lands. I will, however, make further measurements as this is the only thing that has significantly changed. Previous loads were all at 2.800" with this bullet. RS load data availability is very limited, and I hope that I have been erring on the side of caution. I've no means of measuring neck tension other than by measuring the neck i.d. and subtracting it from the bullet diameter, but there was nothing unusual encountered during the loading process. I'm beginning to think that the issue may just be with the OAL of the cartridge. Brillo, 1/2/2, thank you both for your comments too. kind regards Mike.

No, not at all sooty. It's the higher load which was the potential "issue", not the lower load. I'll load up some new, unfired and see how that looks after it's been shot. Not the weather for it today though! Something strange though - have just cleaned and resized the cases with the slight marks and found that the primers slip in with very little effort, so I'll dump them. I'm absolutely sure that I loaded with 42.5gr RS62; the only difference to the other, lighter loads was COAL of 2.825" rather than my usual 2.800". I must have learned something from this, but I'm not sure what 😞 Thanks, Mike.

Thanks Dave. These were once-fired and neck-sized; no lube involved. I also shot the lighter loads at Bisley and they seemed unaffected, but I will give the chamber a brushing just in case.

Thanks Brillo - I hadn't thought of that. I had come to a conclusion that 2750fps was a decent speed for the Scenars (it's certainly accurate at that speed) and higher loads didn't seem to improve matters. I shall try some further loads and maybe see you at Severnside again!

Good day to all. I acquired a Bergara BMP in 6.5CM a year ago and have been enjoying shooting and reloading for it. Range access is limited to 200 yards, but best 5-shot groups of 0.5MOA were achieved using 139g Lapua Scenar, Petersen LP brass and either 40,6 or 42,5g RS62. I have thus been using the lower charge, which gives around 2610fps. The higher charge gives 2750fps. However, with the higher charge, there is some flattening of the primers (not to the extent that the shoulder is squared off though) and a barely discernible ejector mark on the case head (although no sign of "swiping" or sticky bolt lift. The higher loads were behaving fine at Bisley 1,000 yards, but should I be concerned at the faint ejector marks? 42.5gr RS62 doesn't appear to be a hot load - I have read all Laurie's articles and the various posts on here but was wondering (a) whether the faint ejector marks should be cause for concern and (b) whether others using the same combination might offer some observations? Thanks for any thoughts...……..

Bergara 24", Peterson brass, CCI 200: Lapua 139 Scenar: 40.6gr RS62 2630fps 41.9g RS62 2730fps 42.8gr RS62 2780fps 142gr Sierra MK: 42.2gr RS62 2630fps Factory: Hornady 140ELD Match 2670fps

After a year of not having reloaded any .308 I thought I had better get some done and dug out the 175 TMKs. I gave Sierra a call this afternoon on their "Technical Helpline" and asked whether they had yet published any data specifically for the 175gr TMK and N140. Helpful chap advised that yes, they had, and it was 38.1gr to 43.8gr. Somewhat over the Viht maximum of 41.4gr. I don't have a Sierra load manual so don't know whether or not the advised charges are the same as for the 175gr MKs. Although I don't propose to go anywhere near 43.8 I do feel a little more comfortable that my earlier 42.0gr loads may not have been too excessive, and I'm going to start again now with loads from 38.0gr to see how they perform at 200 yards.

Yes Dave, that's it. I did speak to Neil; thanks for the steer.

I think I agree with you. I was perhaps getting unnecessarily concerned. Just shot some more with various charges; the same "cratering" and primer appearance regardless of whether loaded with 38gr or 42gr N140. I shall leave things as they are.

Snakeman, Duey, Phaedra - thank you all very much for your comments, all of which are taken on board and appreciated. I'm not surprised to sense some raised eyebrows at the 175 TMK load...……. it was 42gr NOT 44gr as I originally posted. My apologies; a slip of the finger, although it is nonetheless at the top of the Vihtavuori load table. I'm happy with the 168 SMK load - this was worked up from far lower values and gives me best accuracy although at the high end of the Vihtavuori table and just above the Sierra suggested load maximum. The cratered primers have been evident from day one, with both my own light loads (i.e. starting much lower than the 42.6gr) and with factory loads (which one would expect to be safe in any rifle that they are designed for) - hence my feeling (in the absence of any obvious signs of high pressure) that the firing pin fit is just sloppy. However, all comments noted - I'll start again at 38gr and see if I can achieve good accuracy with a lower charge (even if the primers are still cratered!).

Thanks Dave - that's good of you to respond. He's not too far away, so I'll give him a call!

Good morning, Whilst I have yet to experience a pierced primer, I'm alert to the possibility that it could occur at some stage if primer cratering becomes excessive. In the US there appear to be quite number of people bushing the firing pin channel in the Remington bolt to achieve a better fit (presumably with a new firing pin too) so that cratering is avoided or reduced. This doesn't seem to be a common modification in the UK but I was wondering whether anybody on here knows of it being done in this country (and by whom) or whether it's just not worth bothering about? I always use CCI primers; the image is typical of the cratering observed whether with a light load of 42.6gr N140/168gr SMK or a heavier load of 44gr N140/175gr TMK. Any thoughts please?