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Laurie

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About Laurie

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  • Birthday 10/05/1949

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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. 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 (It has since been replaced by the 7 1/2BR model originally introduced for the 17 Rem which needed a slightly 'hotter' recipe.)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.
  2. Why are you reading and commenting on a topic in the Forum's Handloading section then?
  3. 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.
  4. 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
  5. 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.
  6. 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/
  7. 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.
  8. Ha! Ha! I always said our Leslie is a jammy Geordie b*gg*r!
  9. 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.
  10. There are two factors / ways forward here. One is that you actually need very little shank seated in the neck for single-loading range shooting. I've many times used less than a half-calibre seating depth and got good results. However, for a semi-auto/straight-pull with pretty violent bolt pick-up and feed or a tactical / sporting bolt-action set-up in magazine use and rapid bolt operation, I'd prefer a full calibre depth of seating. With barely seated bullets transport, handle and chamber the ammunition with care to keep the bullet concentric. If this is acceptable, a mere tenth of an inch shank held in the neck is adequate for 30-calibre. Second is the bullet design and how jump tolerant that makes it. The 155.5gn Berger is a very jump tolerant design indeed and if you simply seat it at 2.800" COAL or (if appropriate) whatever COAL the magazine will handle and still feed reliably, the odds are that you will see good results despite horrendous amounts of jump. With any given charge weight, you do lose a bit of MV though. Partially related to this, I've just started load development of 260 Rem in a rebarreled (opriginally 308 Win) FN SPR with a lot of freebore designed to see 140gn VLDs seated optimally. One bullet I'll try is the Berger 6.5mm 130gn AR-Hybrid designed for AR-10 type rifles (or AR-15s in 6.5 Grendel) and which allegedly is very jump tolerant in long-throated (or worn barrel) versions of same. The COAL at around 20 thou' off the lands is 2.927" in this 260 Rem chamber in newly cut form. The rifle's magazine won't hold/feed rounds at the 308's 2.800" COAL, max being something in the high 2.7s (bit remiss for a police / LEA repeating rifle I'd have thought, although the original US FBI spec was for use with Federal 168gn GMM which is under 2.8"). I'll work a load up for the full 2.927" COAL to see what it's capable of then try it again at whatever the magazine accepts and see what that does to groups, MVs and spreads. That'll be around 160 thou' jump - a good test for Berger's claims for this rather (!!) pricey model. As I normally single-feed rounds in this rifle, COAL and magazine OAL mismatches aren't normally an issue for me.
  11. If you're getting 2,700 fps with the 175 SMK and good groups, that really is an excellent factory load. Handloading will allow improvements, but not the large step change often associated with an upgrade from off the shelf ammo. Everything I hear about GGG suggests they produce good stuff - a far remove from RG 155gn 'Bisley Match'!
  12. Laurie

    1 in 12 twist .223 Savage

    The 52gn Hornady match is a good choice for 1:12 twist 223s. The BVSS is an excellent platform too to build an F/TR rifle on should you decide to rebarrel it in the future either in fast-twist 223 or 308 Win (requiring a bolt-head swap - a cheap conversion and 5 minutes work taking the bolt apart and reassembling it). I'd also do a cleaning rod and tight patch check-the-rifling-pitch test on the rifle as it now stands as many BVSSs were supplied with 1:9 twist barrels letting you load 70gn match bullets. Both VarGet and N140 will work with 52s, but are a bit slow burning. (Note too that you'll have trouble getting a replacement supply of VarGet should you like the results as its importation into Europe has been banned since last June, thanks to the EU and its Reach regulations.) In the days when I shot thousands of its AMax predecessor in a 12 twist Remy VS I found that a step faster burning powders, particularly Viht N133, gave me the best results.
  13. Assuming that the 175gn GGG uses the Sierra MK of that weight (as the NRA match 155 does), I'm not too surprised. At modest MVs, the old 175 often gives amazingly good good groups and is very barrel / chamber / velocity tolerant, at least until you try to drive it fast. I shot one of my smallest ever 100 yard 5-shot groups with an IMR-4064 handload with this bullet in 308 Win, moreover in a factory rifle, an early FN SPR tactical / sniper 24-inch barrel job. It was a genuine 0.1-inch and the rifle/handload shot very well at 300 yards too in the benched winter series 'Precision Rifle' matches we used to shoot at Diggle. For short / mid-range use, if you can get factory ammunition with this bullet to perform as well as that, it becomes difficult to justify handloading at times. Unfortunately, the old 175 with its modest 0.243 average G7 BC and the likely modest MVs from the GGG version isn't competitive these days in F/TR at 500/600 (unless shooting in a flat calm) even in club level competition and is ballistically hopeless beyond 800 yards. I quickly found this with my 175 SMK / 4064 handloads, the Catch 22 being that the tight groups came with ballistically sub-optimal low MVs in the 2,600s and the higher MV loads that met the external ballistics requirement wouldn't produce groups under 0.75-MOA. With a good 155 such as the 155.5gn Berger LRBT Fullbore the better long-range bullets up to and including the 185gn Juggernaut, a good F/TR rifle will average under 0.3-MOA at 100. Note the word average as <0.3-MOA means the best individual groups will be under 0.2-inches. My Osprey Rifles (now GS Precision) built Stolle Atlas will still shoot 0.15-Inch groups with the 155.5gn Berger at an MV that has dropped to through throat wear to 3,027 fps (32-inch barrel) despite it having seen nearly 3,000 rounds down the barrel. The average though will be about 0.3. These bullets at suitable velocities will hold under half-MOA elevation at 1,000 yards, most of a 20-round string in quarter-MOA or thereabouts, unless on a range where wind effects also have an elevation component as in Diggle and Blair Atholl when the wind comes from some directions. The heavier 30-cal bullets in the 200/210gn bracket don't usually group quite as tightly or hold as good elevations at long ranges but buck the wind better and so tend to give better L-R scores over a season. Even so, I've seen those 101RC guys who shoot national level F/TR and who generally like and still stick with the old 210gn Berger BT put five shots into ragged holes in loads testing at 100 at Diggle off the bench despite using not at all optimal bipod front-support.
  14. Laurie

    65 creedmoor powders

    That's the sort of SD range I'd expect. I got bit higher but still very reasonable values with Norma large primer brass and the SP Brass will usually give a decent ES/SD reduction. On MVs, bearing in mind that the SP / small flash-hole Lapua brass (which I've no experience of in this cartridge, but do in 308 and 7-08) needs anything between 0.5 and 1.5gn more powder to achieve large primer velocities and there is a report somwehere on UKV in another topic that gives figures from somebody with direct experience that supports that in this cartridge. Given One on Top of Two's SP case MVs are pretty well what you're getting with the more potently primed cases again suggests your recorded MVs are lower than they should be for some reason. Of course, no two rifles even from the same maker produce identical MVs, but even so.
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