Bruce,bruce m wrote:dan,
point no 3 about lube groove location is not clear to me. could you elaborate on that please?
keep safe,
bruce.
Putting lube-grooves in long bore-riding sections reduces the risk of leading.
Bruce,bruce m wrote:dan,
point no 3 about lube groove location is not clear to me. could you elaborate on that please?
keep safe,
bruce.
Do you have a picture of this bullet?deerhuntsheatmeup wrote:I think here is a good place for me to inject that my "clean" bullet, or mistake bullet as some call it, has 5 mini grooves, and that design has served me well with the top groove right in the middle of the bore riding section. Very little leading in a Badger barrel, and very good accuracy out to 600.
Best, DB!
SchuetzenDave wrote:Dan:
I appreciate your work do reduce wind drag by reducing interference from grease grooves.
Yes this will improve the BC and flatten the bullet. While this is more important for very long range shooting or hunting; it does not seem to be as much of a factor for 200 yard Schuetzen or 550 yard BP Silhouette.
Dave, at the turkey line, a high BC bullet certainly is an advantage when the winds are reeking havoc on the bullet's trajectory. And, I would argue that even at 200 yards a high BC bullet, as long as it is accurate, will be an advantage. We all make wind-call errors; and, the less the bullet is moved about, the less effect our errors will have in the long run.
For precision target shooting Schuetzen shooters have found fantastic accuracy from high arcing bullets.
And at a fixed target distance it does not make any difference if I have to set my sights higher to hit the target.
A high-arcing bullet is a low BC bullet. Why is that an advantage? I can't wrap my head around that. A flat trajectory is a better trajectory, especially when shooting at extended distances. Wind speed typically increases with height and wind direction can change with height also. Wind sheer has bedeviled many a marksman, especially at Raton's Creedmoor range.
Of course the risk of reaching a long distance target or chance of too much drop when hunting would be exceptions where I would prefer a bullet with improved BC.
But most of us single shot shooters prefer the classic looks of a rust or hot blued chrome moly octagon barrel.
Stainless steel can be "blued" to look like a fine rust bluing. There are a number of top shooters out there that play in the various BPCR and Schutzen games that have stainless barrels that are "blued." They prefer to not tell anybody due to the fact that they see it as an advantage and don't want others to get the same advantage. I'm the kinda guy that is happy to share all I think I know about things. And, I'm just a dump engineer that chooses function over form. Don't get me wrong, I think the classic look is great and has great appeal, visually, to me, just like most of the guys/gals that play these games.
We do not wish to alter our traditional rifles with a stainless steel barrel.
I did have one exception though. My Money bullet would go to sleep before hiitng the Rams at 550 yards whereas my same weight Paul Jones Creedmore would not do that.
It sounds like your PJ Creedmoor bullet is unstable. Let me share what I learned whilst shooting with a friend down at Pala, CA about 14 years ago. Manny and I had shot together for years in the HP & SB silhouette games. Manny is an excellent shot and meticulous reloader. I suckered him into joining the BPCR games by loading my rifle for him and shooting together at a 3-day match. He purchased two top-quality Shilohs, one in 45-70 and one in 45-90. When he finally got his 45-70, we shot together at Pala during a 3-day, silhouette match. Friday was the first day of match shooting. We started on chickens. Manny got 5, IIRC, he cleaned the pigs, had some highs & lows at turkeys, don't remember the score. He sucked at rams; over the back, under the belly and then he completely missed. I think he only got 2 or 3. Manny's an excellent marksman, so I knew it was his load. When I asked, he told me he was shooting a 30-1, PJ Creedmoor under 62 grains of Swiss 1.5. I told him to load for Saturday with 68 grains. He lives about 70 miles south of the range so he was going home after the match. The next day, with the 68-grain ammo, he knocked down a lot of turkeys and rams. Oh, his rifle has an 18-twist barrel.
It took 3 grains more FFFg to stabilize my Money bullet.
Maybe it would have performed better with reduced grease grooves; but there is no way I am going to put a stainless barrel on my CPA, Rolling Block, 1874 Sharps or 1885 High Wall.
Dave
So what effects the wind drift the most. The BC or the speed of the bullet?at the turkey line, a high BC bullet certainly is an advantage when the winds are reeking havoc
Jim,J.Murphy wrote:....I ran the wind drift numbers for a 10mph crosswind for a typical BPCR bullet and found that 900 fps produced the least amount of drift. 900 fps is below what anyone shoots, but the question comes up as to just how slow can you go and still maintain a stable flight to the rams?
SchuetzenDave wrote:...So what effects the wind drift the most. The BC or the speed of the bullet? A better BC bullet flies flatter and faster.
BC changes constantly as the bullet leaves the muzzle and starts to slow. And, if the bullet is not optimally stable, the actual in-flight BC can be considerably lower than the theoretical BC. That is why marginally stable bullets get pushed about by the wind so much. Since the in-flight BC is a function of the bullet's design, speed and stability, it's a combination of those three that predict how much the bullet will be deflected by the wind.
However the increase in velocity from 1,000 fps to 1,700 fps increases the wind drift of a bullet.
That is why we use high arcing and slow moving cast bullets to obtain less wind drift for target shooting.
I was under the impression that most Schutzen shooters were launching their bullets above 1,400 fps when using smokeless.
From Mike Ventrino and Steve Garbe Reloading Guide:
" To the target shooter, however, excess velocity is an enemy. As can be seen from charts found at the end of this book, wind drift increases as the bullet's speed increases until a certain point is reached. This phenomenon is caused by winds playing on the shock wave which builds in front of a bullet as it passes through the air. Such increases in wind drift continue until velocities pass 1,700 fps and then they decrease."
I beg to differ with the boys, certainly when it comes to long-range shooting. However, I will say that excess recoil is an enemy.
Dan: Who does the bluing of stainless barrels?
The Trinidad gunsmithing school and The Blues Brothers from Prescott, AZ "blue" SS barrels. There might be some others as I've not looked into SS bluing in a while.
Chris,gunlaker wrote:To me the question of highly aerodynamic vs. more traditional style bullets only matters when working with specifics. For instance if you have two bullets of identical accuracy you'd be dumb not to choose the one that reduces errors due to misreading the wind.
I think it becomes more interesting if you make a comparison between bullets like the Saeco 740 and something like the Kidwell Money bullet. This is of course directly interesting to me as I shoot both of them . At distances of 200m/yards, the Saeco bullet is a little more accurate in my rifle. But the money bullet ought to make up for this as the distances increase if there is any appreciable twitchy wind.
Chris.