Ah...hello Mr Bullet, there you go, straight from the horses mouth....not that I would say you were a horse Laurie....more sort of a....errr....oh sheiteLaurie wrote:The US military Judge Advocate General has ruled that HPBT Match bullets are war-legal under the Hague Convention rules on expanding projectiles, only the US military don't like the phrase 'hollow-point' and always refer to the design as 'Open-Tip Match' or OTM for short. Many (most? / everybody other than the US?) countries apparently don't agree and stick to the FMJBT form in their sniper ammunition.
Lapua has made high-quality FMJBT bullets for decades, the B4xx ('Lock-Base') and D (rebated boattail) series amongst the best bullets on the market at one time for TR and similar, but now restricted to a couple of 0.308-inch models it seems, the 170gn B476 and 185gn D46, the 200gn D-series bullet (for subsonic loads) which was available at least a couple of years back no longer listed. Back in the 80s and early 90s, the 150gn B-series lock-base bullets were very popular amongst handloading TR shooters for short and mid-range matches. It was believed that they stabilised quicker than HPBTM models such as the Scenar.
I imagine though that the reason Lapua continued with these design, and still does so in a more limited range, is largely driven my its military ammunition sales of sniper ammunition for customers uncomfortable with the OTM type.
So far as applicability to medium / long-range shooting applications is concerned, Ovenpaa is spot on in saying that it's bullet shape that determines suitability, not any given weight. Berger makes three 168s that all perform at long ranges especially the recently introduced Hybrid. With a class leading i7 (G7 form factor) value of 0.953 (ie nearly 5% less drag than the very efficient G7 'reference design') and a G7 BC of 0.266, that's well ahead of the elderly Sierra 175gn MatchKing design that many erroneously assume is a state of the art bullet in ballistic terms. (The 175 SMK has an i7 value of 1.085 and G7 BC of 0.243, while a form factor lower than 1.0 is highly desirable in any bullet loaded in .308 Win for shooting at 800 yards and beyond on the small F-Class target.) The 168gn SMK is a short-range design and does very well in that role, likewise the many similar designs introduced by its competitors - but there is no 'rule' that says that there is something 'wrong' with 168 or 170gn weight.
The 'ancient' Lapua 170gn B476 FMJBT 'Lock-Base' interestingly manages to outperform its brand new Scenar L competitor, in external ballistic terms at any rate. Lapua lists the B476 as having a G7 BC of 0.249 compared to the brand new (I've yet to see one in the UK to date) GB550 175gn Scenar L at 0.247. There is more to bullet design than BCs alone and Lapua may have gone for features that degrade the form factor / BC to enhance long-range trans and sub-sonic stability / performance, but it seems a little odd that the company's state of the art (2012) design is less efficient than a 30 or 40 year old military model! The GB550 is also 'poor' in relation to Berger designs, the superb 175gn Long-Range BT model being 0.264 and the deliberately blunter 175gn Tactical OTM (designed to perform at 1K in 1-11.25 twist barrels at 2,600 fps when trans / sub-sonic at very long ranges) manages 0.259.
As pointed out, the B476 is a cheap bullet (if you can find any as the main importer Hannams Reloading discontinued the design and sold its remaining stocks off at a large discount about two years ago) and if your barrel likes it makes a great short / mid-range bullet. I imagine that when we do see the 175gn GB550 Scenar L, it will not be a cheap bullet and will be up in the Berger price bracket. Being an 'L', it will be very well made, but it'll remain best used in mid-range F/TR and similar.
I dont suppose you remember the look of terror in my eyes at the Euros, I have only just beaten the lumps out of my shooting skiddies :lol:
Got it all again this year....egotistical my arse, massochistic more like!!
Funny, all I wanted to do was own a Lee Enfield and maybe one day shoot a target at 1000 (Blame Carlos Hathcock's book for that
).Now look at me, garage full of loading gear, bedroom cupboard full of brass, bullets and christ knows what.......would'nt want it any other way....other than perhaps knowing what I am up to..... :cool2:
Eunice tongueout