Reloading 6.5x55SE for elk hunting

[azar]

Hey everyone,

I'm still a rookie at reloading having only started about 10 months ago and having not quite fully developed a load yet (hey, I got engaged and then married recently so I have my excuses).

I've wanted to develop an "elk load" for a while using a 160gr or maybe even an appropriate 140gr. Well, elk season is nearly upon me and after speaking with my brother-in-law today, who gave me an invite to go with him, I've decided I'd like to see what I can do. I have less than two weeks until opening day, so time is of the essence.

After hearing testimony from various sources about the surprising performance of the 6.5x55 even on larger game (especially in Europe) I believe it should be able to handle the task at hand. The elk being hunted will be spike bull and so won't likely be as big as the trophy monsters. And it is my favorite gun and shoots like a dream. For those of you interested it is a CZ 550 American (and it's worth every penny I spent on it and then some).

I'd like the advice of any "Swedish Mauser experts". What would be the "best" bullet for elk hunting in your opinion?

Hornady Interlock 160g
Sierra Pro-Hunter 160g (own a box but I've never attempted reloads with them)
Woodleigh 160g
Lapua Mega 155g
Norma Oryx 156g / Alaska 156g / Vulcan 156g
Speer Trophy Bonded Bear Claw 140g
Barnes XLC 140g
Nosler Partition 140g

I'm pretty sure I could pick up the Hornady 160g, the Trophy Bonded Bear Claw, the Barnes XLC, and the Nosler Partiton locally. Anything else would have to be internet ordered and so would be out of consideration for -this year-. But if you have some input on them I'd love to hear it anyway.

I already have Reloader 22, Reloader 19, and IMR 4350 available to me for powder and Winchester LR, Federal 210, and CCI 200 available to me for primers. I only have mismatched once-fired brass but I could grab a bag of Winchester brass after work tomorrow.

I believe my best bet is using Sierra Pro-Hunter 160g with Reloader 22, Federal 210 primers and Winchester brass as I already own all of these except for the brass. However one of the main reasons I'm asking is I've seen other people say things like "I love the Hornady 160g in my Rem 260, but I prefer the Seirras on the Swede." So, I was wondering which of these bullets people have tried and which they would recommend.

Thanks!

 

[BsChoy]

Any of the rounds you mentioned should be more than adequate with the Norma, woodleigh, and Lapua prob giving you the best ballistics /wieght combo. Most people like Reloder 22 (that's what I use). With heavier bullets its the way to go unless you go slower like H1000, or maybe Reloder 25 but thats it.

Primers, I have always liked federal never out of 1000 primers did I get a dud and again all the primers you listed are great. Winny's burn alittle hotter than others from what I have heard so take that into consideration.

 

[GunTech]

With mismatched brass, you can probably get by if you weigh and sort brass so that you have consistent volume. I'm personally a big fan of WW brass for it's quality and consistency.

What twist does your rifle have? That will make a difference in choosing heavy bullets.

 

[azar]

Thanks guys for your feedback so far.

GunTech, I'm not exactly sure what twist my rifle has. Assuming that nothing has changed in 3 or so years the cz-usa.com website lists the 550 American in 6.5x55 SE at 1 in 8.6 inches. How does that affect which heavy bullets are best?

 

[dcloco]

The "best" bullet is the one that you can shoot accurately in your rifle.

I would go with the 140 gr SST from Hornady.

 

[GunTech]

With that twist, you should be GTG for anything but the longest high BC VLDs. For elk I'd pick a heavy bullet for penetration, or a Barnes TSX. A buddy of mine bagged his elk last year with a CZ 6.5x55. I'll ask him what he used. I've only used my 6.5s on paper.

 

[azar]

dcloco said:
The "best" bullet is the one that you can shoot accurately in your rifle.

I would go with the 140 gr SST from Hornady.

dcloco, I'm aware of the saying and do agree with it. But I don't have time to reload each listed bullet and try them all in a week and a half. Which is why I posed the question here and why I put "best" in quotes. I know it's subjective.

But a shock-tip bullet is what you would recommend for elk? Most shock tips are designed for quick expansion and not something you want to hunt an elk with. For an elk bullet you are usually looking for deep penetration and weight retention (partition bullets, bonded bullets, etc). Varmint are good game for shock tips (what they were invented for, I believe). And a 140g SST from Hornady would be a great deer round too I imagine, but I don't think I'd trust an SST for an elk. But thanks for the input.

GunTech said:
With that twist, you should be GTG for anything but the longest high BC VLDs.

Thanks, but out of curiosity how do you know? What is it about my twist rate that tells you what bullets would be good and what would be better to avoid? It would be a good piece of knowledge to have for future reference. Oh, and by "the longest high BC VLDs" do you mean something similar to a Berger Match VLD 140g? What bullets should I avoid with my twist rate?

Thanks!

 

[Jake in TX]

Azar, the twist in the original Swedish rifles, 100 years ago, was one in 200 mm, about 7.8", and they used bullets of about 160 grains. So with a 1 in 8.6" twist, you should be good with anything up to about 140 grains. I believe you should pick a 140 grain bullet with a reputation for deep penetration and expansion, and develop your load, within your time constraints. Good luck!

Jake in TX

 

[Clark]

If you can hunt a 555 pound elk with a 140 gr bullet moving at 2700 fps, then a 137 pound deer would need a 35 gr bullet moving 2700 fps.

This would mean you could hunt deer with a, well ...er...the .223 would be too big.



Working backwards, if you can hunt a deer with a minimum cartridge of a .243 100 gr bullet at 3,000 fps, then you should be able to hunt elk with a 400 gr cartridge at 3000 fps. A 50BMG can do that.





http://www.alliantpowder.com/reload...typeid=2&weight=140&shellid=1059&bulletid=205

 

[GunTech]

You can calculate the twist requires of any bullet based on it's dimentions, composition and velocity. Idealy, you want a gyrostability factor of about 1.25. This will give you adequate stability in almost any conditions, and not just at Army metro.

Robert McCoy, one of the leading experts on exterior ballistics, wrote a program called McGyro some years ago. You can find various versions of it on the web and in various computer programs. It calculates ideal twist for a given bullet.

The old system of calculating twist is by using the Greenhill formula, which dates back to the late 19th century. It a much simpler formula, but unfortunately is only accurate with roound nose, flat base, jacketed bullets. McCoys formula works with bullets of any construction and design including spitzers, VLD, all copper bullets, etc.

In general, the twist required to stabilize a bulet is related to its length. It is also worth noting that you can often shoot a heavy round nose bullet in a twist that wont stabilize the same weight spitzerbullt because the round nose is shorter for the same length.

Here's an example of a gyroscopic stability analysis. In this case, I ran it for the 6.5 Swede with the 123gn Sierra Match King. The McCoy formula requires that you have a lot of data like nose length, meplat diameter, ogive radius, etc.

 

[GunTech]

Jake,

The old twist works with round nose bullets. It's not fast enough for spitzers of that weight.

Here's a typical 160gn 6.5 bullet. Not at all like the spitzers we are used to.

 

[Jake in TX]

Tod, I think I understand what you are saying. However, the Swedes changed to a 140 grain spitzer bullet in 1941, with no re-barrelling of their rifles. I think a 1 in 8 inch twist will work well with just about any 6.5 mm bullet today. I know my old Swede shoots true with 140 grain Sierra Match King bullets.

Jake in TX

 

[Jim Watson]

I'm with Jake. 140 grain bullet of controlled expansion design, Nosler or competitor.

 

[GunTech]

1:8 twist is a great choice in the 6.5. You'll find that most 6.5 match rifles run 1:8 or faster to stabilize heavy, high BC bullets like the 142 SMK and 144 Lapua Scenar.

1:9 used to be very popular in 6.5 hunting rifles, and thins is more than adequate for lighter hunting bullets, or heavy round nose bullets. Most 6.5 hunters these days seem to have 1:8.5. There no reason to not have a fast twist, unless you will be shooting mid range or light bullets exclusively.

As noted, if you want to shoot heavy bullets, you can always go to a round nose.

Bear in mind, a gyrostability of 1.0 will stabilize a bullet, but not necessarily in all conditions. For example, the M16 opriginally had a barrel twist of 1:14, which work very well, except in arctic conditions, and so it was changed to 1:12. Many 308 rifles, including match rifles, were made in 1:12 twist. But as heavier high BC bullets have become popular, almost all match 308 rifles now made are at least 1:10 to stabilize these longer bullets.

If all copper bullets start becoming really popular, expect to see faster twist rates, because copper bullets are longer than jacketed lead bullets of the same weight, and thus require a faster twist.

Finally, the Swedish Mauser has a twist rate of 1:220mm or 1:8.6. Depending on the bullet, and as shown previously, this twist rate will adequately stabilize a 140gn bullet. The original military loading was a 159gn round nose (B projectile) that was later replaced by a 139gn (D projectile) flat base spitzer. A flat based spitzer requires a slower twist than a boat tail spitzer like the 142gn SMK. The 1:8.6 twist will not adequately stabilize the 142gn SMK, but it will stabilize the 140gn game king thanks to that rounds shorter nose and boat tail.

Here's two rounds in a 1:8.6 twist 6.5. What a difference 2 grains makes (Actually it's bullet shapre that makes the difference). Note that the 140gn Sierrra Game king is actually a better choice than the lighter 123gn Sieera Match kind shown previously. Greenhill would erroniously suggest that the 123gn bullet would be a better choice.

 

[azar]

Wow, thanks everyone. This is definitely educational. The things I never knew about twist rate.

GunTech, You mentioned the McCoy formula requres you to know a lot about the bullet like meplat diameter, ogive radius, etc. Where can you get such data? Or do you have to measure it, and if so, what tools are required? Thank you very much for all the information. From your screenshots it appears you are on a mac, but what software are you using? And do you have a recommendation as far as ballistics software goes for Windows (or Linux)?

 

[dcloco]

Azar - the SST is an "interlock design" as well...here is the info from Hornady. Controlled expansion, interlock, large wound channel, and flatter shooting.

1) Premium Polymer Tip
The sharp point increases the SST’s™ ballistic coefficient, making it faster and flatter shooting. On impact, the tip also initiates controlled expansion at all velocities.

2) Secant Ogive, Boattail Spire Point Profile
It’s a simple fact: bullets that travel faster hit harder. The Hornady secant ogive, boattail spire point profile gives hunters the incredible speed and downrange energy they’re looking for.

3) The InterLock™ Ring
Ensures the core and jacket remain locked solid during expansion, so the SST™ retains the mass and energy needed for dramatic wound channels. Perfected in the famous Hornady InterLock hunting bullet.

 

[azar]

dcloco - Thanks for the info on the Hornady SST. I'll have to give it another consideration.

 

[GunTech]

I measure mostly, but some bullet makers like JLK (Swampy on THR) have the info on their website.

Check out the applications here. There are java versions of McDrag/McGyro, IIRC

http://www.eskimo.com/~jbm/downloads/downloads.html

Here's bullet drag and twist

http://www.eskimo.com/~jbm/calculations/drag/drag.html

 

[azar]

Thanks for those links GunTech. They look like they have a lot of useful information. I have a couple of questions on the link to drag and twist.

I'm trying to get some numbers on the Sierra Pro-Hunter 160g Semi-point. It's basically a 160g roundnose but with a slightly defined tip (I guess that's what makes it a semi-point ).

Since it's a semi-point would I try and measure the Meplat diameter, or would I just consider the bullet "conical" and ignore it? And what would the nose length and total length be? On the webpage it looks like the values are in calibers, but the range of numbers accepted seem too small. I'd imagine the total length would be the measured length from base to tip, which in this case would be 1.260". But inches converted to calibers is 126, which is far beyond the maximum "10" for total length. Or am I missing something?

Thanks!

 

[GunTech]

You caliber is 0.264. Divide the length by one caliber to get the length in calibers. The bullet described is 4.773 calibers long.

I can't find the 6.5 160 SGK on Sierra's web site, but you measure the meplat at what would be the 'equator' of the meplat if it were a sphere. There should be no boat tail. If it's anything like the picture I posted, it probably around 0.200.

Nose length is from tip to the point in the body where it's full caliber (0.264)

With such a bullet, you can probably just use Greenhill and be close, as this is the sort of bullet that was used to derive Greenhill in the first place

 

[azar]

GunTech,

Thanks again for all your help. I checked on Sierra's website and I too failed to find it. Now I think I know why I found it on clearance. It's probably out of production.

So I guess this load won't be too useful, except for the educational benefits. My rough measurements were:
1.260" total length = 4.773
0.400" nose length = 1.515

I believe I now have reasonable numbers coming out of that website. It shows a stability of 1.510 at mach 2.5 with an 8.6" twist. The Sierra recommended load for hunting for this bullet pushes it at 2400 ft/s ~ mach 2.3.

I like the fact that I can run some numbers before spending money on an unknown bullet and attempting to develop a load. How closely do these number match real world usage in your guys experience?

 

[pete f]

Save the headache, get the Nosler partition. its just the one that has 40 years of history of working on big game way out of proportion to its size.

My daughter has two moose with a 6.5, a elk and a black bear. all loaded with 47.0 grains of 4831sc. Federal brass, trimmed to 2.160inch with fed 210M primers. and topped with the 140 partition. It will shoot to about 1.2 inches in my daughters m77 ruger with a 1-4.5 Leupold scope on it. (IT actually probably shoots better than that, but that was she gets and she shoots with the scope at about 2.5 power.

 

[GunTech]

The numbers gebnerated are for Army metro (0 ft, 59 degrees F, 78% humidity and 29.53 inches of mercury). Densier station pressure rtequires more twist, which is why you want a gyrostability factor of 1.25-1.4, which will give adequate stability in any reasonable conditions. Over stabililizing is really only a concern at very long ranges, of with lightly contructed bullets.

If you want a traditional 160gn round nose, Hornady has a interlock version

https://www.hornady.com/shop/?ps_se...&category_id=0d067b6b6a2b64fcbdc1ca279807a686

 

[Shell Shucker]

The answers to your questions might be as simple as calling the bullet manufactures and asking them..........

 

[azar]

GunTech, what would be the issues with "over stabilizing"?

Shell Shucker, it's true I guess I could have asked them. While I'm sure some of them would have said "Yes this bullet is suitable for elk", I probably wouldn't have received an answer like "The Nosler Partition is more suited for elk hunting than our bullet." Then again, who knows? But still, you make a good point.

While I still plan to develop some of these bullets into suitable loads for my rifle, I won't be putting them into action this year. There's just too many things I have to get ready without enough time to do it all. But it gives me plenty of time to get my loads down!

I appreciate all your responses.