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summerman
November 26, 2012, 10:24 PM
www.ballisticstudies.com Go there and go the the knowledge base area. It is a wealth of info on all sorts of cartridges and tests and info. I stumbled across this and it is fantastic. Just wanted to share it with you guys as sort of a way of paying back the great help I have received. It really is great. It goes through different cartridges, history, specs, etc. I have to say it is the best info I have found on the subject. (and I waste a lot of time looking for such info.)

Thanks and check it out.

robertsig
November 27, 2012, 12:15 PM
Wow. I immediately looked up my beloved 6.5x55 cartridge. He doesn't have nice things to say about it.

nate45
November 27, 2012, 12:38 PM
Good site, I read about the .223, 25-06 and 6.5x55 since robertsig felt 'nice' things weren't said about it. I found the information accurate and in accordance with things I already knew from other sources and my own 30+ years of hunting and hand loading.

What was written about the 6.5x55 robertsig, that you found inaccurate? It looked like he just told the honest truth about the cartridge to me and wasn't disparaging about it at all.

robertsig
November 27, 2012, 12:57 PM
I didn't find it inaccurate per se. I'll have to go back and read it again, but some of the other caliber reviews usually have a section where it says "good on this" & "bad on that". I didn't find he liked it for anything.

The history portion is always nice. I just read the .308 between these posts.

nate45
November 27, 2012, 01:14 PM
He owns a 6.5x55 and uses it for a backup rifle for his clients, he must not hate it too bad. He just acknowledges its limitations and stresses the need for using the proper projectile in it.


From http://www.ballisticstudies.com/Knowledgebase/6.5x55.html

Today, my Swede continues to serve as an extremely accurate, mild recoiling back up rifle for our hunting clients. With the benefit of hind sight, this rifle is a reliable killer when loaded with the 140 grain Partition, driven into the major bones of the chest to maximize wounding on tough animals. That said, the Swede is not nearly as forgiving as the .270 Winchester and heavier, especially when wind drift and bullet drop cause shot placement error.

Bart B.
November 27, 2012, 04:08 PM
It's not any different than other forums IMO. Checked out the .308 Win. In the Knowledge Base then learned it has the same good, bad and erroneous info as so many others. Especially the part on pressure numbers on both it and its military brother. No doubt some folks will like and others won't.

Saskhunter
November 27, 2012, 06:06 PM
It appears to be a very good site for informed "opinions" about cartridges, and a reasonable site for actual information. There is, however, a difference.

coyota1
November 27, 2012, 06:52 PM
So far, so good. Gonna read more.

Bart B.
November 28, 2012, 07:26 AM
I just checked out that web site's section on ammunition. Here's their take on powder for reloading:
Hand loading adds another set of variables however; a few myths can be cleared up here. The first is that a change in powder brand will dramatically alter groups, this is simply not true. If the rifle shoots 3” groups with H4831 powder at 60,000psi, it will shoot 3” groups with H4350 at 60,000psi.Really?

I'm curious as to how they're squelching other myths. But first, I gotta find out what they consider myths.

Then I checked out the site's info on epoxy bedding. I fell out of my chair after reading the following:A piece of advice, bedding jobs can sometimes go wrong, whether the job was performed slapdash or performed carefully. Minute points of stress within the bedding surfaces have a dramatic affect on accuracy. In some cases, the person who performed the operation may have used G-clamps to set the barreled action up in the resin. The result is that the action becomes unnaturally stressed when screwed down. This is not an un-common problem. A more insidious problem occurs with parallel walled actions including the Howa/Weatherby, Winchester Model 70 and Sako actions. If the bedding has a 100% fit against the action sidewalls, these rifles will either double group or string laterally. If the fit is too loose, the results are the same. This puts a lot of pressure on the gunsmith although the use of Latex release agents such as Brownells release agent provides the perfect relief for parallel walled actions.No wonder all those folks epoxy bedding flat sidewall actions to full contact with the bedding since the early 1960's for their competition rifles have lateral shot stringing of up to 1/16 MOA at 100 yards range or 1/4 MOA at 1000 yards. We've always thought that sideways stringing was caused by those slightly imperfect bullets we always get and subtle cross winds we can't see. If we put clearance on the receiver sides, then I guess we'll finally get 0 MOA horizontal shot stringing.

What about the stresses on the bottom of our receivers when the barreled action whips vertically changing the force that area puts on the epoxy? Those slightly unbalanced bullets and subtle differences in air density must not be the cause of equal amounts of vertical shot stringing we've believed for decades. Do we have to make clearance all over the receiver bottoms now and free float the whole receiver in the stock to get rid of vertical stringing? How do we affix a totally free floating barreled action to the stock?

No, I'm not sorry I pointed this out. Form your own opinions.

Reloader06
December 1, 2012, 11:30 PM
You just have to take it with a grain of salt. ALL posting on that site or any other are OPINIONS. Subject to human frailty. They are NOT Holy writ.:eek:

My 2c. YMMV

Matt

Adamantium
December 2, 2012, 12:25 AM
Yeah I was looking at the 6.5x55 as well. On the subject of american made ammo...

U.S ammunition brands are typically very poor performers. True velocities from 22 to 24” barrels for Winchester, Federal and PMC 140 grain loads and run between 2400fps and 2450fps. At close ranges, these velocities cause little disruption to conventional bullets on impact, giving up to 80% weight retention and outstanding penetration on medium game. That said beyond 50 yards these brands of ammunition offer very poor shock and slow kills are common.

Add me to the skeptics column too. I also think he places way too much emphasis on BC, which means little at hunting distances. That said, good on him for making a website and speaking his mind.

jmortimer
December 2, 2012, 01:31 AM
For me it was as if Chuck Hawks moved to New Zealand. Some useful generalized opinion but short on facts. Not too impressed. If I lived in New Zealand it would be more useful.

Bart B.
December 2, 2012, 07:30 AM
Regarding that site's claim on 6.5x55 American ammo having true velocities from 22 to 24” barrels for Winchester, Federal and PMC 140 grain loads and run between 2400fps and 2450fps. . . . .

Winchester gets 2550 fps from their factory loaded ammo with 140-gr. bullets. Most folks' factory rifles have bigger bore and groove diameters than what Winchester used to clock that load. So, naturally, they'll have lower muzzle velocities. Such is life with all factory ammo in factory sporting rifles.
Norma's 156-gr. load leaves at 2559 fps in their test barrel.

SAAMI's spec for pressure is 46,000 CUP which converts to about 53,000 PSI. The site states Military 6.5x55 ammunition was loaded to a pressure of 3200 ATM which converts to 47008 psi.

Jimro
December 2, 2012, 09:10 AM
I'm with Bart B. this guy sounds like a gun store know it all. Strong opinions. but some wrong conclusions.

As far as lethality goes, it comes from Accuracy (the 6.5x55 general has it), Penetration (the 6.5x55 has a high sectional density for good penetration), and finally disruption (how big of a wound channel can the bullet expand).

If you look at a 140gr 6.5mm Sierra Game King launched at a sedate 2600 fps from a 6.5 Swede, compared to a 7.62 150gr Sierra Game King launched at 2800 fps from a 308 Win, the ballistic drops are within 1.3 inches at 300 meters, and energy remaining at 500 is actually higher for the 6.5 Swede.

Jimro

Picher
December 2, 2012, 10:39 AM
That said beyond 50 yards these brands of ammunition offer very poor shock and slow kills are common.

Judging by the previous statements he made, this is obviously a typo. Although I suspect he meant to say 250 yards instead of 50, that may not be the correct yardage either.

Picher
December 2, 2012, 11:25 AM
Terminal ballistics is much like drag racing, but in reverse. The more "horsepower" (energy) that can be adequately transferred to the distance within the animal's vitals, the more damage and quicker kills.

Bullet blowup can be compared with excessive wheel spin in drag racing, while inadequate wound channel is caused by too little "horsepower" (velocity & mass) and/or too little bullet expansion. Adequate deceleration within medium game results in the bullet expending nearly all it's energy, while retaining enough to cause an exit wound. Expansion acts like a drag-chute, slowing the bullet more quickly, transferring more of the bullet's energy to tissue instead of anything beyond the animal.

Choosing a proper bullet is more critical when using smaller calibers than, say .308-.35 calibers, because they need to expand more than the larger ones and retain a higher percentage of mass to achieve the same killing power. Blowup and shedding of bullet particles are detrimental to deep energy transfer.

Carne Frio
December 2, 2012, 01:29 PM
Thanks for that link, Summerman. If terminal ballistics
is an interest of yours, you need to check out this link.
It is in another forum and the ballistics part is moderated
by a well known professional.:D
http://www.m4carbine.net/forumdisplay.php?f=91

Bart B.
December 2, 2012, 01:48 PM
Regarding the 6.5x55 cartridge, how many readers know that was "the" round for the original biathlon shooting stages at 300 metres? It was (and still is) a tack driver. And many European 300 metre free rifles won all the medals in international 3 position competition with that round. It was a favorite in the USA until the .308 Win. replaced it. 'Course the IOC stopped 300 meter centerfire rifle shooting after the 1972 (or 1976; I now forget) Olympics and went to 50 metres with .22 rimfire ammo used in other short range events.

Jimro
December 2, 2012, 06:13 PM
Bart B. It is kind of a shame that the old sports with full sized rifles have all gone to rimfires. Watching a Finn unsling a biathlon model Mosin and clean the target is always humbling. A lot of national pride used to hang on who had the best riflemen on the 300 meter free rifle line.

I'm learning the hard way that techniques that work on a full size rifle to deal with recoil do not translate well to airgun shooting. And there is absolutely no way I would want to shoot a center fire rifle like an air rifle. I wonder why the IOC made the change? Maybe to open up the sport to countries that have incredibly horrible firearms laws?

Jimro

Bart B.
December 2, 2012, 09:43 PM
Jimro, the IOC stopped using 300 metre centerfire free rifle matches in the 1970 and just used 50 meter smallbore ones. They did that so countries could more easily and cheaply build ranges. A 50 metre rimfire range will fit in a building. But a 300 meter centerfire range needs a few miles of safety zone behind it.

The only time the IOC bowed to pressure from protesters was when they (and the International Shooting Union) changed the "running boar'' match target from a picture of a running wild boar with scoring rings centered on its heart area to a standard round bullseye target. Animal rights protesters didn't like seeing that great looking lithographed picture full of bullet holes well centered on those scoring rings. Scores wentup as the middle of the bullseye was easier to see as that boar was pulled across a 10 meter opening. Half of the runs are slow (target visible for 5 seconds), and half are fast (target visible for 2.5 seconds)