Like Eric, I have never seen anyone at a rifle match of any kind using solid projectiles.
I'm finding this bullet debate to be very interesting in that it shines a light on many things I'm not familiar with and the intricacies of the bulletmaking world.
Still I must quibble with this quote and it' soft-repeated variants. Every weekend hundreds of shooters across Canada and the US participate in Creedmoor, Schuetzen and BPCR Silhouette. Each and every one of them shoots solid bullets. True, they're not solid copper, gilding metal or unobtainium, which I'm certain Brian and Ed both meant, however if we're talking precision, and being precise, we must be precise in all areas which would include our public statements. The above statement being the example.
It may be sorting gnat **** from pepper, but us blackpowder guys have feelings too! (And for some reason the smilies won't work for me so just know I'm trying to interject some humour, not be a dink!)
Last edited by BigUglyMan; 06-21-2009 at 01:44 AM.
I have several questions about barrels, but I do not want to detract from the stated purpose of this thread - a discussion of solid bullets. Might I suggest that a separate thread on barrels and barrel production be created....
One of the immediate realizations made upon hearing Hay's dismissal of the feasability of high explosive propellants for small arms use, was the default 4150, or 416, alloy justification. Their primary reccomendation has little to do with the application. Other than ease of machining, there is nothing to reccomend them for a high temperature environment.
... and in the interveining period, initiated with the jet propulsion age, huge metallurgical advances have gone entirely untapped by the barrel industry.
Not only do we have alloys that will withstand the environment with impressive results, but by moving to a cobalt based alloy (as opposed to iron), the degraded physical characteristics associated with elevated temperature service ie., reduced tensile and yield strength, are significantly reduced.
Now one might say, "A $450 barrel is disposible anyway, why not just burn them up, and replace them... who needs a super-alloy when I only plan on using conventional propellants?"
To the precision long-range shooter, it is the second half of the benefit package that has significance. A barrel which maintains it's physicals over a large temperature spread has a bearing on target dispersion patterns.
I'll jump in on the barel issue then with a quick question that have been lurking in my head for a while.
If there are barrel materials that can withstand hotter temps and higher pressures, what incentive does a barrel manufacturer have in switching over to a material that lasts longer and needs to be replaced less frequently. Obviously they would need to charge more for each such high tech barrel. Can he dio it with his existing equiment. If not, how do I , a single consumer, get a manufacturer to make that financial commitment?
I clearly see the benefit to me - a high intensity shooter - I put 1,700 rounds through a F-Class 7WSM in the last 2 years before I took it off and recycled it (most folks would say I went at least 500 rounds too many in this barrel but she was a hammer til teh end when it died all at once as I was told it would). During the same time period I put at least a 1,000 rounds through my .260 and a .308 for practice so that I didn't shoot out the barrel any earlier than necessary. To me a barrel is a $650.00 dollar consumable (the blank runs 350-400 but you still need it chambered and head spaced to your rifle).
Granted, I would also strongly consider switching to different - meaning more intensive - chamberings or hotter loads to shoot if I could get a barrel for my 7WSM that would last 2,500-3,000 rounds. Am I correct in connecting the link bewteen the new barrels, the statement about new propellants, and greater velocities... If so, now you've got my attention in a big way.
I knew the "debate" characterization of this thread was something of a misnomer, so I will just monologue until someone has a question/challenge.
In the early development of the cobalt family alloys, it was discovered that a welding contact, made from copper, would induce localized micro-cracking if the temperature came anywhere close to solution temperature, and this holds true for all cobalt alloys. In a bore, this is obviously a bad thing.
From experimentation, I can tell you that nothing beats copper as a projectile bearing surface. How was this incompatability issue to be resolved? A friend, from the polymer industry, drew my attention to a TiO2/SiO2 gel used as a lubricant/protectant in hyper-velocity APSD munitions. When loaded into a cartridge, it deposits a continuously renewed ceramic layer in the throat. Presto! No more compatability problem... and then there were the other benefits. Fouling is virtually non-existant, and projectile exit velocities were consistantly single-digit in variation.
Once again, some of you might be saying to yourselves "My barrel does not really foul to any great extent now, and my MVs are pretty consistent also.".
My answer is that you are still all throwing away that barrel following a few thousand rounds due to heat-erosion. This will make even a 416 barrel live for alot longer (I do not actually know how much longer.). The trick is to utilize a shell casing that is designed to disperse the gel. As it happens, this shell casing has approximately the same life as the barrel itself... that is a single shell casing. Is anyone tired of buying, and reworking, quality brass?
I will go to rifling geometry unless anyone has a question at this point.