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Only here have I ever heard of the 243 being a barrel burner. I dont get it. I will refer you to post number 13 of this thread.
Please explain to me the reasoning behind this whole throat burning in a medium caliber burning a relatively small volume of powder compared to bore size.
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j chappell,
Earlier posts notwithstanding..... the accuracy requirements for 1k yard COMPETITIVE shooting are quite stringent.... quite a bit more than for the average shooters.
Whatever the causes.... and I don't pretend to know all the answers here, but I DO have daily and frequent contact with LOTS of guys who shoot Long Range games (See my tagline.), the smaller calibers do indeed tend to burn out the throat a lot sooner than the larger bores TO THE POINT THAT THE NEEDED 1K YARD COMPETITIVE ACCURACY STANDARD IS LOST.
Part of the reason for this is (As I stated previously.) the smaller calibers have to be driven pretty much as fast as you can get them in order to get full advantage of their ballistics.... otherwise, there would be no reason to choose them over the larger diameter bullets for 1000 yard shooting. Because of this (Needing max or near max charges for a given case volume.) the throat of the barrel takes a LOT of abuse and erodes out much faster than does a larger bore.
Now.... the non-competitive shooter or varmint hunter may never notice this erosion effect on accuracy until it reaches a point that the competitive target shooter would long since have sent this tube off to be replaced.... but have no doubt that it IS a noticeable and very well known effect among long range competition folk. If you have doubts or questions.... ask either the competitors who regularly shoot Long Range Highpower (LR is defined as 800 to 1000 yards.... 600 yards is Medium Range.), LR F-Class, Palma, and 1k BR or the gunsmiths who regularly get orders from their customers for barrels to fit the action they made for them.
Falling right in with this.... At the NRA 2008 MO State 600 yard Championships in October I was on the same point as Steve Satern, one of the up and coming Highpower, Palma, and BR barrel makers and LR gunsmiths out there. Steve was shooting a .243 built on a Tube Gun. Him being a barrel maker and me being a LR bullet maker we had lots to talk about.....
As he was shooting he was stating that he was close to the 1500 round mark on the barrel he was shooting, and that the X-count at 600 was dropping.... meaning that it was time to change barrels (NOTE: If the X-count was dropping at 600, then this barrel was probably already long past usability for competitive 1000 yard work.).
He also related that he heard complaints from a lot of shooters and customers that they really liked the idea of the 6mm chamberings, but did not want to replace barrels so often. His comment was basically to the effect of... "Accuracy costs money... How accurate can you afford to be"?? (See my previous comments about this.)
One last note: The comments above regarding the need for speed and barrel burnout with 6mm chamberings are PRIMARILY related to Long Range, 800 to 1000 yard competition.
For 600 yard competition there are indeed several smaller caliber cartridges that are the cats meow. The DIFFERENCE is that for 600 yard work not nearly as much initial velocity is needed for the 6mm projectiles to stay competitive with the larger diameters. Smaller cases with less powder and much less throat erosion is the norm for dedicated 600 yard work..... but again, it's all relative. The larger bores using smaller cases also get correspondingly longer throat life in the 600 game.
Best regards,
Swampy
Garands forever