July 3rd, 2011

30 Caliber vs. 7mm for Long Range — Litz Offers Analysis

Bryan Litz, Ballistician for Berger Bullets, has authored an excellent article on bullet design, What’s Wrong With .30 Caliber?. This story originally appeared in Precision Shooting magazine, and now can be read on LongRangeHunting.com.

In this article, Bryan analyzes the design of long-range bullets, from .22 to .30 caliber. He notes that while 30-caliber bullets can have very high ballistic coefficients, 30-caliber bullets must be very heavy to match the BCs of the 6.5mm and 7mm projectiles. As the chart below shows, it takes a 240gr 30-caliber bullet to match the G7 BC of a 180gr 7mm VLD. But most 30-caliber shooters don’t use those ultra-heavy projectiles because the recoil is excessive and because it takes a monster cartridge burning lots of powder to drive 240-grainers to optimal velocities. Litz notes: “Heavy recoiling rifles are harder to shoot accurately. Even if a shooter overcomes the mental aspect of heavy recoil, the ‘system’ is more sensitive to minor imperfections in shot execution. This may be another reason that drives .30 cal shooters down to the ‘middleweight’ 190-grain class bullets instead of the proportionally heavy 220-240 grain bullets.”

Ballistic Coefficients

Litz concludes that the heavy 7mm bullets are a better choice than the biggest 30-calibers (except in unlimited weight “heavy guns” where recoil is not a factor.) Bryan writes: “Even a moderate 7mm chambering is capable of delivering 2800 to 3000 fps with the heavy 7mm bullets, much faster with magnums. The heaviest .30 cal bullet requires a big magnum just to get to 2800 fps. So the first problem is: you can’t get the heavy .30 cal bullets going as fast as the heavy 7mm bullets! Even if you could get the same muzzle velocities from the heavy .30 cal bullets, it would take much more powder to do it, barrel life would suffer, and you’ve only achieved parity with the 7mm. The various negative effects of the incredible recoil are really just the ‘nail in the coffin’ for the heavy .30 caliber bullets.”

Bryan’s Updated Second Edition Ballistics Book
If you are interested in learning more about bullet design and ballistics, check out Bryan’s book, Applied Ballistics for Long Range Shooting. This highly-respected resource, now in its second edition, includes experimentally-measured Ballistic Coefficient (BC) data for over 236 long range bullets of various makes. The new edition of Applied Ballistics was upsized to 7″x10″ and Bryan added two new chapters, while updating the existing chapters. Bryan’s book comes complete with a CD containing Version 2.0 of the Point Mass Ballistics Solver. CLICK HERE to order Litz’s book and CD for $49.95.

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July 3rd, 2011

OutdoorsTrader.com Offers FREE Gun-Related Classified Ads

OutdoorsTrader.com is a FREE alternative to Gunbroker.com and AuctionArms.com for selling firearms, magazines, optics, and hunting gear. Set up like a Craigslist for gun stuff, OutdoorsTrader.com lets you place free ads for buying, selling or trading guns, ammunition and parts. Conveniently, you can search ads by state, or even by zip code proximity.

Because OutdoorsTrader.com is relatively new, there are relatively few listings at present, but we expect that to grow. We clicked on “Oregon” and found a couple dozen listings, mostly handguns. A search for “Colorado” revealed a half-dozen listings, half rifle, half pistol. So OutdoorsTrader.com has a long way to go to challenge the big players such as Gunbroker.com and AuctionArms.com. But we’re glad OutdoorsTrader.com exists — it’s always a good thing for consumers to have more options.

OutdoorsTrader.com classifieds

OutdoorsTrader Charges No Fees, Unlike Gunbroker
We hope OutdoorsTrader.com becomes successful. Gunbroker.com is fairly expensive for the seller, who pays when the item sells (at auction). On an expensive rifle, Gunbroker.com fees can be significant. The cost to sell a $3500.00 rifle on Gunbroker.com is $56.88.

By contrast, OutdoorsTrader.com is free to join and entirely free to use. Once an account has been created, the user may post ads of his own and also leave replies on other posted ads. OutdoorsTrader.com has been around for a couple years. We hope it gains in popularity so it can provide more competition to Gunbroker.

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