Need .260 gas gun load help w/120gr. range bullets

[nickw]

Hello,
I'm new to reloading centerfire rifle cartridges other than .223. For .223 I use pre-sized / prepped brass that just requires a primer, powder and bullet. Really easy. I have no loading equip. for .260 so any advice is appreciated. I load .223 on a Dillon 550B and pistol ammo on Dillon presses as well.

I've got a JP LRP-07 gas gun rifle in .260 coming. 22" 1:8 twist bbl. JP is recommending lighter weight bullets like the 123gr. scenar and VV N550 @ 2800fps. I was looking for some other loads with the lighter weight bullets to try. I don't really want to spend a lot of time on case prep if I don't have to. Rifle will be used for LR / precision rifle matches. If you can be as specific as possible, I'd appreciate it.

I did do quite a bit of research (searching forums) and there is a lot of data out there for .260 bolt gun loads, but not gas guns (at least I couldn't find it). I understand that a good load for a bolt gun may not be good for a gas gun, issues with port-pressure and such.

Thanks in advance for the help.
Nick-

 

[Greg Langelius *]

Re: Need .260 gas gun load help w/120gr. range bullets

I have found (in my bolt gun) that the Nosler 120gr Ballistic Tip is both highly accurate and terminally explosive on 'Chucks. I have tested with the Hornady 129gr SST, and while I was not committed to a proper development sequence, did determine it had good potential for both accuracy and hunting effectiveness, more likely better suited to larger game. While I use H4350 and 140-ish bullets for my bolt gun, I suggest that Varget (which burns somewhat faster) would likely be a better choice for your gas system, and pass on Hodgdon's min/max data range of 36.0gr to 39.0gr. I think that the Winchester WLR primer would be consistent enough, and confirm common advice that primers should be seated flush, and not be permitted protrude beyond the cartridge's base surface when loading for a semi with a floating firing pin.

Greg

PS, While you're at it, don't overlook the Sierra 120gr MatchKing. A bit more compact, it may help with OAL considerations. For very effective short(-ish) range varmint applications, the Hornady 95gr V-Max is an accurate bullet that doesn't seem to mind being driven hard and fast out of a 1:8" twist barrel.

 

[BCP]

Re: Need .260 gas gun load help w/120gr. range bullets

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Nick W.</div><div class="ubbcode-body">I understand that a good load for a bolt gun may not be good for a gas gun, issues with port-pressure and such.

Thanks in advance for the help.
Nick- </div></div>

I wouldn't worry about that. If you look at the loads people are using in their gas guns they are almost always just as hot as the loads in bolt guns. I know my semi AR loads are just as hot, or hotter than, stuff I use in my bolt guns. You have to keep in mind that you need a load which will cycle your action reliably.

The only real difference I can think of off the top of my head will be OAL. Some people I've talked to that shoot 260 with the heaver bullets load them well over 2.8 overall, but if you want them to feed out of your magazine they will have to be 2.8. There is a little wiggle room, but not much.

FWIW n550 looks to be similar in burn rate to IMR 4350, and all the loading charts I've checked recommend slower powders so that should give you an idea of where to start.

 

[Heman]

Re: Need .260 gas gun load help w/120gr. range bullets

My NRA Course gun (and also shoot it occasionally for LR) is a Medesha .260 upper with 26" 1:8 Kreiger. I run the 123gr SMK with 36.5gr of N150 for the 200/300/600 line. Works like a charm. Brass I use is Remington .260 brass although I find it to soft so I'm necking down RA-60 surplus brass for that load. For the 600 and 1000yd line I run a 142gr SMK with 45gr of H4831SC in necked up Win .243 brass shoots very well. Just cause I like the GI brass I'm going from .243 brass to LC 07 LR brass. I run a tubbs CWS so that helps alot of preasures. As far bullets for LR precision work you may want to look at the JLK 130's they will have a better BC than the 120-123gr class bullets but may work better than the bigger 140-142 class due to your 22" barrel and not having all the length to burn the slower powders.

You're going to find a .260 gas gun is great fun to shoot, and if you've made wind calls with a .308 the .260 is even better.

 

[nickw]

Re: Need .260 gas gun load help w/120gr. range bullets

Guys- Thanks VERY much for the replies. All were extremely helpful. I'm looking for one round that will shoot well from 100 - 1000 in my 22" 1:8 bbl. I'll have to look at the JLK 130's...thanks for the suggestion Heman.

On a side note...I've got a fair amount of once fired Hornady .308 brass from their TAP line. Can I neck this brass down?

Thanks again,
Nick-

 

[Heman]

Re: Need .260 gas gun load help w/120gr. range bullets

Before I comment on the brass, the 130gr JLK's are a VLD bullet so they probably won't be able to be loaded to mag length without suffering some powder loss. I didn't think about that when I posted as all of my LR shooting is done single feed as per NRA rules. A friend of mine (Dave Nirode) shoots them in his 260 bolt gun very well.

As far as brass yes .308 brass can be necked down, you will probably need to turn the necks however. But you may not, just have to see. As stated I now use LC07 LR brass or RA-60 brass for my .260. The only comercial brass is Remington and the pockets just seem way to soft for me. The other option is necking up .243 brass, but then you are using some of the thicker shoulder brass to form the neck and you will get the dreaded doughnut after a couple of firings. For a gas gun your best off using the hardest brass you can find.

 

[Casey Simpson]

Re: Need .260 gas gun load help w/120gr. range bullets

Norma 130 grain bullets shoot superb in my 6.5x47L. I recommend them highly.

 

[Greg Langelius *]

Re: Need .260 gas gun load help w/120gr. range bullets

Yes you can, but the likeliest outcome is a bit of thickness in the neck walls. I suggest necking in two stages, 308 to 7-08, then 7-06 to 260; but honestly, it's a lot of work.

I use Rem 260 brass with no big issues, though the primer pockets have a mild tendency to open up a bit easily. I'd worry about this more if I were driving my brass at max loads. But my strategy is to use additional barrel length, rather than higher powder charges, to make up my velocities. So max loads are far less necessary.

I have necked down Win 7-08 with no issues, and necked up Win .243 with similar success. If I've encountered the neck-up-donut problem, I honestly haven't noticed it. I run about 5 or 6 reloads on my cases, and the loads are about a grain below max, which my explain the lack of detectable donuts.

Other makers, including Lapua, make .243.

Also, I use a F/L die, but back it off so I'm only sizing about 60% of the neck's length. This leaves the neck-to-shoulder area expanded and does not work the brass in that area. This may also be postponing the donut, or at least any problems on its behalf. Another thing it does is to center the neck in the chamber.

The base of the cartridge also doesn't get worked quite so low, possibly better centering the cartridge base in the chamber, and perhaps reducing tendencies toward case head elongation.

Theoretically, this practice should result in a case which chambers more concentric and parallel with the chamber/bore axis.

My chambers are all cut to SAAMI spec.

Greg

 

[nickw]

Re: Need .260 gas gun load help w/120gr. range bullets

Thanks for all the info guys. Heman was kind enough to let me contact him off list for a big email Q&A. I really appreciate that Shawn. I'm going to try some 123 scenar's today loaded by Corbon in the performance match line. If they shoot, I'll likely try and duplicate this load. The 107 SMK also looks interesting. Thanks again everyone.
Nick-

 

[xQuest]

Re: Need .260 gas gun load help w/120gr. range bullets

Nick,
I just now came across your post of 4/10. Sorry that I did not read it sooner. Have you recieved any worthy advice?
I recommend Nosler brass. It's currently out of stock at Powder Valley, but it's the best price at around $47 per 50. The thing about Nosler is that it comes completely sized, chamfered, outside mouth deburred, and inside primer pocket deburred. I checked each one with a L.E.Wilson case gauge and they were all perfect. Additionally, they were very close in weight case-case. I highly suggest you shop around and get some. Note that if you fire them at max or near max pressures, you should consider annealing as you would any good brass. VV N150/550 is right up there with Varget. I use both powders. I've had good results with 123/139 Scenar and best with Hornady's 140 A-Max in my DPMS upper. I highly suggest that you single stage this round. It really demands attention to detail not assured by a progressive system. Watch your pocket depth (keep them uniformed). I conducted an experiment with different primers, keeping all other components the same. I was supprised to find that the tightest group came from WLR. The others I tried were: WLRM, and CCI 34. Have fun with your 260 and above all, BE SAFE!
XQuest