6.5x55 Swedish

slimjim · Posted: Fri Nov 21, 2014 7:56 pm Post subject: Re: 6.5x55 Swedish

MacD wrote:

From my own reading, all other factors being equal, SD is the primary determining factor in penetration. However, all other factors are hardly ever equal so expansion, weight retention and retention of symetry as the bullet passes through tissue and bone can significantly alter the affect of high SD. Putting rifles aside for the moment, high SD designs are used in direct fire artillery and tank rounds to improve penetration in everything from concrete to armour.

Thanks for the link. My comment regarding SD not being a reliable factor for determing penetration is not from reading, it is from conducting hundreds of bullet tests and measuring expansion and penetration. Take two bullets with the exact same SD impacting at the same speed, one expands to double its diameter and the other does not expand at all. Which bullet will penetrate farther should be obvious. If bullets did not expand, then SD is a good determinant of penetration. Your example of military rounds shows this. The military's penetrating projectiles are not designed to expand.

The .277 150gr Accubond Long Range has about the highest SD any 270 bullet can have. Yet, the majority of .277 bullets, even those with 1/2 the SD will out penetrate it.

Another myth busted, when a bullet impacts at a slower velocity, it typically penetrates deeper because it expands less.

Elvis · Posted: Fri Nov 21, 2014 8:33 pm Post subject: Re: 6.5x55 Swedish

there is good info on 6.5x55 on terminal ballistics site.

MacD · Posted: Fri Nov 21, 2014 8:52 pm Post subject: Re: 6.5x55 Swedish

Slim let me reiterate that I really learn alot from your posts of your experiments. Keep it coming and I for one will be most appreciative.

Elvis · Posted: Sat Nov 22, 2014 2:07 pm Post subject: Re: 6.5x55 Swedish

140grn Nosler partition into forward shoulder area= dead animal
according to site mentioned above..very interesting write up on the swede.

slimjim · Posted: Mon Nov 24, 2014 7:11 am Post subject: Re: 6.5x55 Swedish

MacD, I enjoy exchanging information and sharing experiences with members of our forum family, also. Your comment spurred additional thought and consideration. You gave me some additional ideas on to approach the SD issue. Thanks.

MacD · Posted: Wed Nov 26, 2014 2:31 pm Post subject: Re: 6.5x55 Swedish

Pictures as required. Note how the magazine follower keeps the bolt from closing on an empty mag.

Azar · Member Joined: Jan 04, 2010 Posts: 275 Location: Utah

I think you got a very good deal Mac!

She looks great. Let's hope she shoots even better. Wink

Elvis · Posted: Wed Nov 26, 2014 5:16 pm Post subject: Re: 6.5x55 Swedish

very tidy.

slimjim · Posted: Wed Nov 26, 2014 5:49 pm Post subject: Re: 6.5x55 Swedish

That was quick MacD. No 5-day waiting period? She is a beauty and should be a lot of fun. Looking forward to the range report.

Vince · Posted: Wed Nov 26, 2014 6:40 pm Post subject: Re: 6.5x55 Swedish

Methinks you are going to get a lot of enjoyment from this little lady Mac.

Suzanne · Posted: Wed Nov 26, 2014 10:52 pm Post subject: Re: 6.5x55 Swedish

Wow those sights look like fine ones to try out, what a great fit too. I see it's all bedded and ready to go. Stock is in great shape...I think I want one. Can't wait for the range report, hope it's not too snowy!

Suz

Aloysius · Posted: Thu Nov 27, 2014 1:56 am Post subject: Re: 6.5x55 Swedish

Very nice. Don't forget when you've sighted her in to try also a few shots with the back orifice removed so that you get a much larger hole and then tell me if she's fastpointing or not.

MacD · Posted: Fri Nov 28, 2014 12:58 am Post subject: Re: 6.5x55 Swedish

May have to wait awhile for the range. Only ammo available local is 140 Core lokt. I will have to get my dies and components and roll my own.

slimjim · Posted: Fri Nov 28, 2014 6:35 am Post subject: Re: 6.5x55 Swedish

So what is wrong with taking for a test drive with the CoreLokts and keeping the brass? Aren't you itching to pull the trigger?

chambered221 · Posted: Fri Nov 28, 2014 4:40 pm Post subject: Re: 6.5x55 Swedish

Sectional Density is the ratio between bullet weight and diameter, add shape into the equation and you can determine it's Ballistic Coefficient !!!

These mathematically arrived numbers give us a comparable look at judging bullets ability to fly through the air and retain energy.

What most tend to ignore is the fact that these numbers are only good when comparing bullets of the same construction.

Pick your favorite bullet, shoot them in multiple calibers and weights at the same velocity..... the one with the highest SD will out penetrate the rest.

SD figures were never meant to be used as an overall indicator for penetration like some use them.