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Laurie

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About Laurie

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  • Birthday 10/05/1949

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    Hpartners1998
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    York
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    F-Class, BR, and any form of target shooting that involves a scoped rifle, but doesn't require shooting offhand

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  1. The basic Russian Murom LR primer works very well in the 284 Bruce - that's the KVB-7. I've also used the so-called Magnum version of this model successfully in 284 and Shehane, the KVB-7M. The 7 and even the 7M are very 'mild' models and that's generally what works best in this cartridge even with charge weights in the mid to high 50s grains. Before anything else though, try the CCI-BR2s you have. This is a mild and very consistent model. Avoid the Rem 9 1/2 and 9 1/2M, both very 'hot', also the Federal 215 LR magnum and its 215M 'match' version. Exceptionally 'hot' and in a cartridge the size of the 284 tend to produce large MV spreads. (Might suit a mid winter 600 fixture with temps at minus 10 though! ) I'm assuming you're using a realtively easy to ignite powder such as Viht N165 or the now lost H4831'shortcut'.
  2. Laurie

    6.5 creedmoor and RS62 temperatures

    Yes, I have Hunter and have used it in a few things over the last few years. It'll be one of those tried in the 260. It flows too well for the RCBS Chargemaster even with David, Shooting Shed, Bonwick's thingie used, so it (and other Ramshots) sees my old Hornady 'Competition' volumetric measure recalled to use. In this tool, the Ramshot grades produce remarkably consistent weights.
  3. Laurie

    6.5 creedmoor and RS62 temperatures

    I agree RS52 is very different to N550, but VarmLR says he was using RS62, very similar burn rate to the 4350s, N150/550, and N204 but single-based of course. It's interesting (and encouraging) that you find N204 so close to H4350. I intend to do some comparative tests in 260 Rem next winter looking for alternatives to IMR and Hodgdon H4350. RS62, Norma N204 and URP, Viht N550, Alliant Re16, and Lovex SO65 look the most likely possibilities. In the US, Re16 is being quoted as a very close match to H4350, very temperature tolerant - allegedly as good as the best of the Hodgdon / ADI 'Extreme' grades, and giving somewhat higher MVs than H4350 in suitable cartridges. It is of course double-based like all Alliant and Norma powders and I haven't seen a % value anywhere as yet, so may be hard on barrels if loaded up fully. Like the Norma grades, Re16 is manufactured by Bofors in Sweden, but has Bofors / Alliant's new 'TZ' treatment technology to reduce temperature change effects. It is finally available here and I've bought a couple of pounds to try. Norma powders have always had a reputation for being very temperature affected. I certainly found that with Alliant Re15 (same thing as Norma 203-B) in 223 some years ago even in our climate. Whether the newer grades such as URP are better I don't know, likewise whether Bofors / Norma are respecifying existing grades or improvements are restricted to the new ones only available under the Alliant brand name with 'TZ' (Re16 and 23 so far). Even if they've not said so, most propellant manufacturers are looking to reduce the temperature sensitivity of their ranges. Vihtavuori is allegedly in the process of doing so for all of its rifle powders whether N100 or 500 series. So far the only one they're admitting to is the new N565, but rumours say other older grades have been 'done' too. The company is keeping very tight on this and will only announce it if and when the entire range has been modified. Whether any such change affects other characteristics is an interesting (and important) question given that Viht has a reputation for lot to lot consistency so no need until now to check if a new lot needs any load adjustment. Returning to N204 it is one of the lower nitroglycerin content Norma grades at 4.5% by weight, so should give a small performance boost but without significant extra wear and tear. The new(ish) URP is one of the three 'hottest' Bofors/Norma grades at 10.5% alongside 217 and slightly less than MRP's 11.5%. URP is stated by Norma to be slightly faster burning than 204, and its applications are similar looking at Norma's No.2 manual published last year. In some applications, it gives little or no MV increase over 204 at Norma's listed maximum loads; in others, MV is significantly higher. Lovex SO70 (being the old Accurate-4350) would seem the most likely 4350 alternative from that source, but was always known to be the slowest burning of the 4350 trio. I've never found it as satisfactory as the IMR and H versions perhaps partly for this reason. SO65 though looks interesting. Explosia's burn rate chart shows it on the same horizontal line as H. VarGet which is clearly nonsence. It makes a very poor VarGet replacement in cartridges like 308 Win and superficial digging in Explosia's Lovex loads data tables shows it's much more at home in higher case capacity to bore ratio cartridges like 7X64 and 7X57mm. I've used it for some time in a long-throat 7mm-08 F-Open rifle with very good results indeed with the 150gn Lapua Scenar-L as a short-distance load. I note with some interest that Shooters World in the US which is now distributing Lovex powders under US-orientated SW brand names (SO65 becomes 'SW Long Rifle' for instance) raves about it for use in the 6.5mm Creedmoor .... https://shootersworldpowder.com/long-rifle/ .......... the classic H4350 application. One problem is that Explosia's own loads data omits many cartridges people here might want to try it in, 260 Rem and 6.5mm Creedmoor for instance. Shooters World is building up its own pressure-tested data-sets https://shootersworldpowder.com/wp-content/uploads/shooters-world-manual.pdf which fills some gaps. There's a good selection of Creedmoor load combinations.
  4. Laurie

    6.5 creedmoor and RS62 temperatures

    Yes, all Alliant 'Reloder' series rifle powders are 'double-based' Most come from the Bofors, Karlskoga, Sweden plant and a smaller number from Nitrochemie in Switzerland (ie the 'Reload Swiss' people). This goes back to a US government pre-WW1 anti-trust ruling that split the USA's single propellant / explosives combine up. In smallarms propellants, all single-based products and manufacturing facilities went to what later became IMR and all double-based equivalents went a new outfit the Hercules Powder Co. Alliant ATK eventually bought this side of the business and rebranded its products 'Alliant'. There is no legal requirement these days (at least AFAIK) for Alliant grades to be in this form, but the company has stuck with it. Likewise, all Norma powders come from Karlskoga and are also double-based. Norma quotes the nitroglycerin %s and they range from low single figures to barerly into double figures. (Viht N500 series are generally considerably higher.) All of the new IMR 'Enduron' powders are also 'double-based'. There is a tendency it seems for new additions / results of recent R&D to have at least some nitroglycerin in the recipe. I imagine this is partly about performance, but also all the other things that prpopellants are expected to do nowadays from accepting temperature stability to copper fouling reducing additives.
  5. Laurie

    6.5 creedmoor and RS62 temperatures

    I've got a couple of pounds of Alliant Re16, yet to try it - but on paper it looks a good option in this bracket. This is one of the new Swedish (Bofors) made Alliant grades with the company's 'TZ' temperature technology and is claimed to be as good as H4350, possibly better in this respect. As to applications and burning speed, it's very close to H4350 but can usually produce higher MVs if loaded to maximum levels. See: http://bulletin.accurateshooter.com/?s=Alliant+Reloder+16&submit=Search Norma (all of whose powders are made by Bofors) appears with a couple of additions such as URP to be offering an unchanged range from say 20 years ago without any updates, and this seems rather unlikely given the way all propellant manufacturers have ugraded their products in recent years. So, it may be that today's Norma N204 and Alliant Re16 are one and the same thing. (I have some N204 on the way too and will be able to compare their grain structure, density, and performance.) Right now, the reintroduced Norma grades are considerably cheaper in the UK than Alliant powders, worth considering by British forum members. (Re15 and Norma 203-B are one and the same thing for instance.)
  6. Laurie

    Pierced primer! Trip to the gunsmith?

    The original model SR primers were designed for the low-pressure .22 Hornet in the 1930s. Many such rifles had weak firing mechanisms as they were converted rimfires or built on elderly small single-shot Martini or falling-block actions. So primer cups were made of a soft brass alloy and are 0.020" thick to ensure reliable ignition and they were plenty strong enough for 22H pressures and the similar cartridges that followed it like the Bee. When Remington introduced the .222 Rem cartridge with its 52,000 psi peak pressure in 1950, the company decided its model 6 1/2 primer was inadequate for these pressures, so introduced the model 7 1/2 'Magnum' primer for this cartridge. It had the same explosive pellet as the 6 1/2 so the 'magnum' bit was solely the increase in cup thickness from 0.020" to 0.025" and maybe a bit tougher alloy. (It has since been replaced by the 7 1/2BR model originally introduced for the 17 Rem which needed a slightly 'hotter' recipe.) The 'soft' / weak models are: CCI-400 Rem 6 1/2 BR Murom KVB-223 / older copper coloured PMC SR Winchester WSR (0.021" cup thickness) - but only more recent brass colour WSRs, older silver ones were thicker / tougher. Federal 205s and 205Ms are nominally 0.225" thickness. Everything else is 0.025" The thin / weak models shouldn't be used in higher pressure cartridges such as 223 with full loadings. For decades Remington printed this on its 6 1/2 packaging but dropped it in recent years for some reason. So the OP has fired thousands of his loads with a too-weak primer and had no problems no doubt due to a mild load / pressures. Fair enough, but there will be little margin and as another post points out, there can be the occasional faulty or thinner example or production lot. Personally, I know what my choice of primer would be for 223 - always a thicker model - but in this case, I probably wouldn't worry ............ until or if it happens again.
  7. Why are you reading and commenting on a topic in the Forum's Handloading section then?
  8. Laurie

    Best reloading manual

    They can vary a lot - I just saw 3gn difference in a maximum load for a 6.5mm Grendel combination, ands believe me that is a huge amount in this tiny cartridge. In this case, much of that may be that US SAAMI MAP is 50,000 psi and European CIP is around 8,000 psi higher. 5-10% variances between manuals aren't unusual and can depend on make of brass (different internal capacities), primer model, powder lot variances and the test barrel internal dimensions. The components (case + primer) differences can be great enough to make a major change and that's why most manuals say somewhere in the introductory text section that the printed loads apply only to combinations using the specified items. Occasionally, a manual says that the loads apply to that make of case and that only. Speer does that for 243 Win saying that there is an unusually wide spread of case capacities in this cartridge and that its loads are specifically for Winchester brass only and no others. Sierra tends to use Federal cases whenever available for the cartridge and in contrast IME these are usually on the heavy / low capacity side increasing pressures / reducing max loads. Also, of course whether the supplier is super-cautious or wants to impress the manual owner with maximum possible MVs. I like it when pressures are shown as this gives some indication on this issue, also whether as sometimes applies a maximum load is determined by how much powder the case holds with the particular bullet at that COAL not the PMax generated. Then there are 'dodgy' cartridges, usually elderly originally military such as 6.5X55, 7X57mm, 7.5X55mm Swiss etc where the testers / compilers have to decide whether to provide max loadings for modern rifles, for SAAMI which is often lower, or for some yet lower PMax in case the shooter has the oldest, weakest rifle model that the cartridge was ever chambered in.
  9. Laurie

    NRA RCO Handloading Rule

    I'm intrigued by a spot-check on 6.5X47L as it's pretty difficult to get outside of the MoD envelope at least with anything other than light varmint bullets. 6X47 or various other 6mm wildcats could easily be an MV issue though. Everybody 'thinks' HME / ME on this topic, but remember there is an MV ceiling too that in effect rules out 204 Ruger, 22-250 Rem and many SAAMI / CIP sixes with anything less than the heavier match bullets in fast-twist barrels. https://nra.org.uk/nra-bisley/ranges/latest-range-information/range-regulations/ 1,000 m/s = 3,280 fps
  10. Laurie

    New 223 lapua brass

    Foxpig has got it right. You do need to chamfer the inside case-mouth edges as with any new case to ease bullet seating. IME, new Lapua brass has very consistent OALS, so I never bother with trimming. Neck tension out of the box is usually very tight indeed with this make irrespective of cartridge, too tight in fact, so inside lube the necks and run them over either a mandrel expander or the expander ball in your sizer die if using a conventional FL die set. Some people FL size and if you're using that die's expander for the previous step, you might as well size at the same time. Again, IME Lapua cases of all calibres usually arrive in pristine condition, so IMO FL sizing isn't required. If there are some 'dinged' necks, size them - although if the ding is big, better to carefully open it up manually beforehand with the bullet in a same calibre inert round or dowelling. Foregt flash-holes, primer pockets, necks, weight and all the case-prep tips unless you're loading for a custom rifle. Some of these practices may be useful / ncessary with other makes but not Lapua's 223 Rem cases - you've paid for Lapua to get it right in the factory and no rectification is needed. Oh, and do inspect cases closely. Lapua is good, but the very occasional shoulder or neck flaw escapes factory inspection - a slight longitudinal fold is the most likely. Better to junk that case now before doing the other steps or worse only noticing it on final inspection after priming, charging, bullet seating etc.
  11. There's nothing new under the sun in firearms they say ..... and the Russians have reinvented the British 19th Century 'Paradox' form (smoothbore barrel with the last few inches before the muzzle rifled). Of course, anything's possible when it is driven by suitably wacky firearms laws. https://www.thefirearmblog.com/blog/2019/05/24/new-russian-cartridge-366-magnum/
  12. Laurie

    NRA RCO Handloading Rule

    This isn't a new requirement. Some 20/25 or so years ago and long before shooter competence certification was required, somebody in the MoD discovered many civilian users of its ranges used handloaded anmunition. A standard self-certification pro-forma was produced and handloaders and/or users of non-NATO spec factory ammo had to complete it. If commercial factory ammo, details from the manufacturer had to be entered; if handloads details of which loading manual data was used. It was a simple form on the lines of I .....[name].................. hereby certify that my ammunition has been loaded in accordance with data from the ................. handloading manual and is within MoD range specifications. There were spaces for calibre, bullet weight, manual (or chronograph) provided likely MV, resulting ME. Many of us duly made out these forms, one for each cartridge / handload recipe and took them with us to MoD range sessions. AFAIK, this requirement has never been rescinded and is still in force. I have never heard of anyone being asked to show the relevant authorities such a declaration and within a year or two nobody bothered about it. On the other hand I'm glad to say that I've never been on an MoD range when a serious overload has caused a major firearms failure and death or injury in which case somebody might have asked for the relevant declaration. I have been near an action blow-up in an early European F-Class Championship meeting at Bisley when Steve Donaldson's rifle action from one of the smaller US action makers in a 308 Win F/TR rifle blew part of the receiver out. The NRA RCOs carted the bits off, fired cases and unused ammo and quizzed Steve on the load. The load and the ammunition / case conditions were soon given the all-clear and metallurgical testing of the remains of the receiver showed flaws that had caused the failure and a warning notice was issued about the make and model of action.
  13. Ha! Ha! I always said our Leslie is a jammy Geordie b*gg*r!
  14. Laurie

    Starting loads...useless?

    There are starting loads and starting loads depending on the source. A generation ago, Hodgdon only gave maximum charges with the instruction to subtract 6% to get a starting load, an exception being H110 where only 3% should be deducted. Over many years, I've concluded Hodgdon got that pretty well right so a 46gn maximum 308 Win load should start around 43.2gn and a 24.5gn 223 max would be ~23.0gn. This approach was apparently too technically demanding for some customers and/or the lawyers didn't like it, so Hodgdon now quotes staring loads in grains like everbody else. Taking some of its 168gn 308 Win loads at random its current starting loads run from 5 to 9% below the stated maximum depe3nding on the powder grade. Look at Hornady's manuals though and you get a very different approach. The lowest loads quoted are much more than a 10% reduction. Its 7th edition (sticking with 308 and 168gn bullets) lists H. Varget from 32.6gn to 44.0gn - a difference of around 23% which I find ludicrous. Apart from taking forever and wasting a lot of barrel life in working a load up by 11.4gn, the lowest charges will be grossly inefficient and most likely inconsistent as they are running at well below the powder's 'happy' pressure band. Other manufacturers / sources quote ranges anything in between these extremes. The original Hodgdon advice remains pretty valid. Unless the bullet or powder manufacturer says otherwise in relation to a particular cartridge-powder combination, something in the 6-10% band below maximum is usually a suitable reduction. There are exceptions either because the powder is very low-pressure intolerant and/or it is a high volume case design as in many over bore capacity magnums being loaded with very slow burning propellants. In such cases the quoted starting charge is also the minimum charge and must not be reduced further. Doing so risks very inconsistent results and in extreme cases a dangerous one that sees charge detonation instead of burn and pressures that will destroy the firearm. Sierra Bullets whose people know more about safe load development than most say that charges should be worked up in step sizes that are c.1% of the quoted maximum, so 0.4-0.5gn for max loads of say 46-49gn, 0.2-0.3gn for 223 Rem size charges. On approaching maximum loads, reduce that further to say 0.2-0.3gn for 308 Win size charges, 0.2gn for 223 size. On precision, traditionally it was said that maximum loads / pressures rarely or never gave the best groups and this has become a handloading 'rule'. This was largely down to the poor quality of most mass manufactured rifles after WW2 where locking lugs didn't bear evenly on the receiver, or in many twin lug Mauser type actions, one lug didn't touch the receiver at all until pressures approached maximum, then it would touch randomly producing fliers. This condition shouldn't apply to modern factory rifles hopefully and certainly not at all to custom stuff built on small production volume actions. Often such rifles group very well indeed somewhere near maximum loads and MV extreme spreads are generally smaller with higher charges. However, any individual rifle's best precision occurs in a series of charge / pressure / MV 'nodes' or bands as charge weights rise, usually 1-1.5gn apart in a 308 size cartridge / charge weight. So a starting load may or may not be right on a 'node' and could give superb groups. As charges rise, groups open up until the next node appears. Often the very highest allowable charges / pressures fall between nodes, so a lower charge weight gives best results. That's what on-range load development is about / for - ie finding precision and small MV spreads at an optimum velocity for the firearm and the application. As One on Top of Two says, the reason for quoting starting charges and working loads up from them is primarily about safety as individual barrels / chambers and cartridge component choice other than the powder can see considerable pressure and hence usable / safe maximum charge variation between individual rifles. Only a fool starts with the maximum - but there are fools out there sadly.
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