Home Forums Reloading Big Game Rifles 308, RL17, 200 gr bullet

I'm working on a high performance mag-length heavy bullet 308 load with RL17 powder.

I like the 208 AMax but to fit it in the Rem magazine (2.825" on mine) requires pushing it way down until the ogive is almost entering the neck. Takes up a fair amount of case volume.

So I went looking for something else with a fairly high BC, and a little shorter length. Three bullets look interesting.

200 gr Speer SP, 1.27" long, BC .546

200 gr SGK, 1.40" long, BC .550

200 gr Accubond, 1.485" long, BC .588

For comparison, the 208 AMax is 1.53" long, BC .648


I have some of the SGKs, and ABs on hand so I'm starting off with them.

I laddered up with the 200 SGK with some pretty good velocity numbers. Only fired two rounds at each level for velocity figures. Will get them on a target soon.

Here's the data,



M700 VS 308Win
Factory bbl/throat, cut to 20.5"

200 gr Sierra Gameking
Win brass
CCI 200
2.81" oal
Reloder 17

50.0 gr - 2610, 2621 (15' from muzzle)
51.0 gr - 2662, 2663
52.0 gr - 2721, 2714 (fairly heavy compression, just a hint of bolt resistance after firing, no ejector imprint or primer flattening).

I loaded up 10 rounds at 51.5gr for an accuracy check. Estimating about 2700 fps MV. This will deliver approx 1900 fps/1600 ft-lbs at 600 yards, in local atmo.



There will be updates to this as I go along.

Good info, thanks for posting it.

Considering the topic of the post, anybody heard the latest on the Seekins BDL to blind mag setup?

Interesting. I have been thinking of trying the 180AB in my 77RL 308 with R17 powder.

Wow, impressive velocitys.

Thanks for the info................DJ

Shane,

I don't believe Speer's BC claim on that one, but I can't really prove out my doubt. It's a flat base and doesn't seem to have a long ogive.

mathman

Those are some pretty smoking numbers for a 200gn out of a 20.5" barrel. I'll have to check, but I think I can run ~2700 with Berger 185 BTs out of my 26" barrel using Varget, but that's pushing it.

...............I`m not surprised at his #s from the shorter 20.5" barreled 308. RL17 increases velocity in the 308 as it does for the WSMs.

69 gr of RL17 averaged 3234 fps using the 155 gr Berger VLDs. And 66 gr RL17 averaged 2953 fps with a 180 gr SST. Both loads from my 16.5" barreled 300 WSM Ruger Frontier carbine.........Not bad ay?

Gotta luv todays new hi tekkie powders.

I've run RL17 in my 338-06, but not the 308. May have to do it for fun. If it works so well in the 308, would it not work well in the 338 Fed? But, even Alliant's numbers don't come close to 2700 with a 200. They are showing 2641 with a 180gn and 2739 with a 165.

Did some more testing today.

308 Win
Win brass
200 Accubond, moly'd
2.815" oal
RL-17
20.5" bbl

50.0 gr - 2620 fps (heavily compressed, no pressure signs)

Here's a visual. Left to right, 200SGK loaded to 2.81" oal, 200AB loaded to 2.815" oal. 208 AMax, 200AB, 200SGK.


Put some rounds on target at 100 yards today. 5 rounds each of the 200 SGK at 2700 fps, and the 200 AB at 2620 fps.

Wind was full value at 15-25 mph. So you can see the lateral dispersion is noticeable. Just keep in mind the wind conditions.



I pulled the last shot a little high on the ABs.


Both of these have potential.

The 200 SGK at 2700 fps will deliver about 1900 fps/1600 ft-lbs at 600 yards, 4500' el.

The 200 AB at 2620 fps will deliver about the same. ( lower MV, but higher BC)


In direct comparison on the other end of the spectrum, I loaded 130gr Barnes TTSX to 3100 fps. At 600 yards it delivers about 1825 fps, 960 ft-lbs.

I'm a little skeptical too. I haven't actually shot any of them, just stated the published numbers.

Shane-Thanks for an informative post. I have some 200gr TSX that I've been meaning to load up for moose. Your numbers tell me it should have enough oomph to get the job done, but there might be better options. Time for me to load 'em up and shoot 'em.

Ballistically these loads are quite impressive but I don't know that I'm comfortable with your powder charges. Alliants website lists 48.7grs of RL-17 as a max load for a 180gr bullet:

http://www.alliantpowder.com/reload...ight=180&shellid=80&bulletid=189

and gets about the same velocity out of a 22" barrel with a 180gr bullet that you are getting out of a 20.5" barrel.

Using a 20gr heavier bullet with 1.3grs over the max listed load for the lighter bullet almost always means you are shooting at higher than normal pressures. I see where you say that you aren't getting pressure signs but you ARE - VELOCITY IS A PRESSURE SIGN! If you are getting the same velocity with heavier bullet and heavier powder charges in a shorter barrel no less YOU ARE USING HIGHER PRESSURES! Your rifle is probably a very finely fitted gun that won't show pressure signs on cases as a less well blueprinted one might.

I wouldn't use your powder charges with that weight bullet!..................................DJ

Those 200gr TSX fall between the 200 AB, and 208 AMax, for length. Long suckers I guess being all copper. I'd still look to RL17 for best speed. Might only get 48-49gr in there.

I'm only neck-sizing my brass to get all the powder volume possible.

dj,

Actually my rifle is a loose fitting factory Rem with a long throat. Also I'm using roomy brass. It all adds up.

You need to also understand the nature of RL17 and it's impregnated retardant. It kinda changes the rules. The powder is labeled "For Short Magnum Rifles".

I've been loading for over 30 years, and I understand and appreciate your concerns. I'm pretty well versed at finding pressure and backing off a couple grains. RL17 is something you have to work with to understand a little. It really takes the peak off the pressure curve. Well, that's what the experts say anyways, and I'm seeing it in application.

MM
What is your opinion of the 180 gr Nosler Ballistic Tip for long range? My 30-06 shoots them really well.
whelennut

I'll be the first to say i was skeptical about the claims of added velocity possible with RL17, but glad I gave it a try.

I hear talk of a series of rifle powders with this technology applied (impregnated retardant). Things are more interesting as we go along. We haven't reached the pinnacle of smokeless powder technology yet.

Whelennut,

I'm not a big hunter. I'm a shooter and always interested in performance. My hunting days were with old technology 243, 30-30, 30-06 stuff.

The 180BT has a reputation for good accuracy, and has a decent BC. Reports I've read about on game performance seem to run the whole gamut. Just depends who you ask. Like a lot of bullets I suppose. I would guess at 308Win velocities they would work rather well.

MM, I understand that the new propellants can give higher velocities than normal. I still don't think I'd go 1.5grs over the manufacturers max load listed with a bullet 20grains heavier. And wouldn't expect to acheive the same velocity the manufacturer did with a bullet 20grains lighter in a barrel 1.5" longer.

Maybe I'm cautious but I still have both eyes and all my fingers after reloading for 35 years......................DJ

I wouldn't recommend these loads in an M1A. A lot of 308Win book loads are geared toward that port-pressure requirement.

There are a bunch of us doing R&D with RL17 in the 308, and 7-08 with the heavies in boltguns. My findings are in line with everyone else.

I imagine the book loads are built with the lowest common denominator, and for good reason. Running heavy brass, tight chamber, short throat is always going to cause more pressure with equal charge than light brass, loose chamber, long throat, and moly.

Bottom line, if you aren't comfortable with it, don't do it.

I am completely comfortable with it, or I wouldn't do it either.