Ultimate build: Which chambering for a SHORT action: .260 AI or 6.5-284

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Ultimate build: Which chambering for a SHORT action: .260 AI or 6.5-284.

Yep, that's the question....if I do end up actually doing this ultimate build, it will be on a short action for sure.

Leaning toward .260 AI, due to reading about how 6.5-284 has trouble feeding reliably in a short action (due to the fat case, etc.). Then I could shoot either .260 rem factory or .260 AI handloads.

But if it would feed reliably, I'd rather do a 6.5-284, so that I don't have to fool with fire-forming, etc. That's the big *IF*. 6.5-284 is normally done in a long action.

I'm not concerned about shooting the longest VLD bullets because this would be built specifically to optimize for the Nosler Accubond LR 129 gr., so those aspects of feeding reliably through the mag are not a big concern. This bullet is what I'd call very long (1.350"), but not super-long.

So anyone know for sure whether 6.5-284 will feed reliably through a short action? Anyone know? This would probably be built by Proof Research, which I think would be on a Defiance Machine "Rebel" action, if that helps.

http://www.nosler.com/accubond-long-range

Oh, my bbl length will be 27" if that helps. Hunter, so want that second followup shot - not a single shot.

Dark horse is .260 rem (regular). Really dark horse is 6.5x55.

Edit: I think .260 AI is the winner - same ballistics as the 6.5-284 (by the time you seat the bullets deeply enough for them to feed through a short action), but (1) longer brass life, (2) no reliability issues, and (3) less reputation of bbl-burner if I ever go to re-sell.
 
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The best person to answer most of your questions is the smith you get to build the rifle. Especially if they have ever worked with either cartridge.

While the 6.5X284 is technically fits in a short action, it works better in a long. You run into the same problems that killed the .284 Win, when it comes to heavy long bullets and limited magazine space. You have to get a larger than standard magazine box if you want to use it in a short action and I think Wyatt's makes one that will work the Defiance action since it uses a M700 footprint.

.260 AI would be the one I'd choose as well out of your two choices if that's all I had. Don't expect much more than 100-150 fps gains at most from standard .260 Remington hand loads. AI rounds don't always feed the best but if you use a single stack magazine you'll improve your odd of not having any issues with feeding. For the .260 AI I'd probably go with something that uses AI magazines to avoid the feeding issues.

I imagine you've already researched this article on Terry Cross. I'd talk to him about the .260 AI first. I'm sure if you sent him an email discussing your build he might give you a few pointers, but his website says he's not taking on new builds or customers at this time.

If resale is an option you want to keep open, then stay away from AI cartridges. Standard cartridges are easier to resale than any kind of wildcat cartridge. Expect to get 1/3-1/2 the cost of the rifle back at best if you ever try to sell it, selling custom rifles is rarely a winning proposition.
 
Thank you sir. All excellent advice. Yes, I've decided against the 6.5-284 already. Now it's between .260 and .260 AI. No, hadn't seen that article - looking at it now. The only other possible chambering perhaps for this build is 7mm-08 AI (thoughts?).

That feeding issue is the big one for me... First off, if there's any chance of a feeding problem, I won't do it - I will do .260, not .260 AI. There is a 100% chance that this will be a fixed internal box magazine with hinged floorplate, not detachable, as if a factory Rem 700 BDL or similar. So, in this mag configuration, to your knowledge, are the feeding issues present, absent, or unknown?

As for resale, yeah I understand you may get half back if you're lucky, but all things being equal, you'll still get $200 more from a chambering without a reputation as a barrel burner than you will from a chambering WITH a reputation as a barrel burner, deserved or not.

Also, should I use that Rebel action, or try to find a Rem 700 Titanium action?
 
There is always a chance of feeding issues with an AI cartridge. The taper of the rifle cartridge is there to aid with feeding and extraction of the case. Ackley Improving the case removes most of the body taper and changes the shoulder. This is why center feed or single stack magazines work better with the AI cartridge, since it keeps the cartridge more inline with the chamber to start with.

The components you use to build your rifle is your choice. That said buying the Defiance action will probably be easier than locating a Remington TI action, and possibly cheaper. I'm not sure why you would want a TI action anyway?
 
Lighter weight, perhaps? Why else would there be?

If what you say is true, that there is *always* a potential feeding issue with an AI, even with a single stack mag, then I will definitely run with .260 plain. I don't want or need any hangups when fast cycling.
 
Lighter weight, perhaps?Why else would there be?
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IMO the weight savings of a TI action doesn't justify the cost over a regular M700 action for building a light rifle. Not when you can buy custom actions that weigh nearly the same as a TI, in the price range of a blueprinted M700 TI action. Plus let's face it if you're building a rifle with a 27" barrel, it's going to be heavy anyway.

It would help if you'd spec out the build a little more, your current description is pretty vague. 27" barrel, what twist and contour? What stock are you thinking of using? What is the main use of the rifle, you said "hunter" but your not really building a hunting rifle unless the majority of your hunting is done from a blind or stand. The rifle you're building will be best used off of a bipod or bags since it will be extremely nose heavy.

Who knows there may never be any feeding issues with the .260 AI, many who build AI cartridge rifles never have any. There is a fix for most issues, you just need to have a smith that is familiar with what they are. Plus you need a smith that will stand behind their work 100%. I also tend to stick with gun smiths that are local now instead of shipping them off, it makes it easier to get problems corrected.
 
Jamming a long round into a short action seem's silly to me, you could be causing unnecessary pain and suffering to yourself by limiting bullet choice and having to seat the bullets way off what will get you the best accuracy.

I don't think fire forming of brass is much of a head ache in AI cals, I know it can be a huge pain in other cals causing you to have to neck turn and other nonsense, but the AI forming is pretty straight forward.

But many opinions online seem to be that the 260AI doesn't seem to give you much gain to be worth the work. I can't remember what the gain is, but it'd be up to you to decided. If I was worried about fire forming an reliable feeding, I'd be inclined to just go for a standard 260 Rem, you can buy Lapua brass and be done with it.
 
Jamming a long round into a short action seem's silly to me, you could be causing unnecessary pain and suffering to yourself by limiting bullet choice and having to seat the bullets way off what will get you the best accuracy.
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This +1. Actually to take full advantage of the .260, you want to seat the bullets really high and fill the brass with powder so not to leave any air gap. This mean the final round will be over 3" in length for a very tight fit in a short action.

But many opinions online seem to be that the 260AI doesn't seem to give you much gain to be worth the work. I can't remember what the gain is, but it'd be up to you to decided. If I was worried about fire forming an reliable feeding, I'd be inclined to just go for a standard 260 Rem, you can buy Lapua brass and be done with it.
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This + 1 again. The .260 is one of the few calibers that really does not benefit much from the AI 40 degree shoulder.

My vote is for a .260 long action.
 
A 260 long action?
Hell,might as well just build a 6.5-06 or go with the 6.5-284 if you're using a long action.

I love the 6.5 Creedmoor in a bolt action,along with the 260 Rem,but my 260 is in an AR-10 platform.
My barrel for my 6.5-06 build shipped yesterday,so it should be finished in a few weeks,as soon as I finish fitting/finishing the stock.

I've never been sold on the AI chamber for any caliber,but then,I'm not a speed freak when it comes to ballistics.
 
There's plenty of room for a .260 in a bolt action mag, it gets a little crowded in an AR magazine but it still works. You aren't going to gain a lot of performance by seating the bullets longer than magazine length. If you keep things simple, they'll simply work.
 
Well y'all have convinced me to go with plain old .260 rem (if I do it at all). Thanks.

Plus let's face it if you're building a rifle with a 27" barrel, it's going to be heavy anyway
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Nope. Carbon fiber wrapped. Very light rifle. Probably an 8.5 twist, maybe tighter. Whatever the minimum necessary to shoot Accubond LR 129s is. Proof Barrel. Proof / Lone wolf stock. No, this is a hunter. I erroneously assumed that when I said Proof would built it, that it went without saying that it would have the CF barrel - that's their main raison d'etre. The base steel will be Mike Rock or whatever they recommend. I think it will come in well under 7 lbs bare.

If I go with long action, I will go with .280 rem or .280 rem AI (or maybe 6.5mm-'06). No this is a short action build. Lighter the better. Although, .260 in long action sounds interesting; never heard of that.
 
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I did a little research on Proof Research last night. The way I figure it you'll be close to 7lbs before you even add the scope.


.264 cal carbon fiber barrel 26" (they don't show a 27" for .264 calibers) light Sendero will weigh 3lbs.
Proof research stock weighs 22 ounces. (your not getting an 18oz stock unless you go with the Summit Youth/Ladies stock)
Remington 700 TI with trigger, action screws, magazine, BDL trigger guard will save 4oz over the standard M700 SA which is 2lbs 4oz. So lets say 2lbs.
Add 3oz for bedding compound and pillars (guestimate based on what a 22oz McMillan Edge weight finished out)
4oz for Talley LWT mounts.

6lbs 13oz just for the bare bones rifle.

Add 13oz for Leupold VX3 4.5-14 or 16oz for 3.5-18 Swarovski Z5 like used on Proof Research rifles.

Now your at 7lbs 10oz or 7lbs 13oz without adding a sling, bipod, or rounds which will get you closer to an 8+lb all up hunting rifle. It's pretty light don't get me wrong, just not as light as you think it will be.

I can build a rifle that light or lighter without having to spend $900 on a CF wrapped barrel or $5000 plus to have Proof Research build the rifle. I don't think there is enough benefit to the CF wrapping on the barrel to justify the cost. Nor do I think you actually need a $5000+ rifle to ensure you have a lightweight hunting rifle.
 
I think the recommendation of a standard .260Rem is a good one. I went through the whole process/debate myself and ended up with a .260 Rem on a 700 action.

Do yourself a favor, do a lot of research on Proof before you plunk down your cash. I know a thing or two about Carbon Fiber and I do honestly believe that a $800 budget on a Bartlein barrel with some careful design of the profile, will get you a longer lasting, more durable, and only a little heavier rifle. You can certainly get a M700 into the 6.5 pound area with a 24 or 26" barrel built by a smith who specializes in lightweight builds.

I hunt with a .338-06 bolt action that is just under 7 pounds with the optics mounted. Had a 7mm-08 M700 that was 6.4 pounds with optic.

BTW, my .260 wears a 21" barrel and I shot my Pronghorn with a 130 Accubond at 680 yards last year.:eek:
 
I've been hunting for a mighty long time and over those decades I've found that I don't like long barreled rifles. The longest I have now is 22 inches and the most recent is a 260 with a 20 inch barrel. Longest shot with that 260, so far, was a feral hog at 487 yards. The rifle itself is a Tikka T3 Lite Stainless. Since I couldn't buy that rifle in 260, it was put together by a smith. Money well spent. Nice and light.
 
Thank you all....

I don't want to bug the Proof guys until I have the $$ and am ready to do a possible build. As a business owner, I know how much enormous amount of time I waste with tire-kickers, and don't wish to do that to others trying to make a living until I'm serious about buying. You guys, OTOH - I will gladly waste your time. :D

The Proof/ABS method & materials of CF-wrapping is known to be superior to the Christensen method (for the same or less $$, to boot). The dual/interlaced CF-based materials dissipates heat better. Christensens are ok, but Proof definitely better, say many in the know. See, e.g., SnipersHide, 24HourCampfire, LongRangeHunting, etc.

This is the ultimate just one build, if I do it. It *MUST* have the long bbl to squeeze every bit of performance out of a non-overbore round like .260, and how do you think a 27" pencil barrel will perform (and look)? I don't know for sure (not ruling it out), but I don't think very well. So for the same weight (or just almost), I can have a stiff & long bbl, using CF-wrapping.

Cost isn't an issue on an "ultimate build", by my definition. The whole point of an ultimate build is "without regard to cost; with regard solely to performance, etc.". However, lighter IS better. So I'm taking what you're saying to heart (taylorce1). If I can truly get a non-CF bbl that is both lighter and equally accurate in the 27" range, then I'm all about that instead, without a doubt. I just need some real numbers and more input / experience. I could be convinced to go as short as 26" or as long as 29", potentially, but I think 27" is where it's at for this build, give or take 1/2".

There is no doubt in my mind that I could build a 20 or 22" rifle with: equal accuracy (cold bbl), lighter weight, and more external ballistic performance, from a pencil hunting barrel in .26 Nosler or similar in a long or magnum action. But I do NOT want such a rifle. I don't want a barrel burner, and I want a short action. If I'm gonna plunk down that much for a barrel, it needs to last a looong time, and retain re-sale value, which non-barrel burners do. The chambering is decided now - .260 rem. As is the approx. bbl length. I will consider if you still have a cogent reason why I should budge from these, but I'm starting to get fairly well set on those two decisions. So keep the input coming if I'm just all wet here.

If it helps, the two hunting scenarios for this rifle are (1) Plains & desert speed goats & mulies; and (2) High-alpine (mostly above treeline) steep & mountainous sheep, goats, ibex, etc. So both are open-ish, where the long bbl won't hamper me. Shots will ALWAYS be rested - never a snapshot. I need lightest weight with very good long-range performance. I want to have a PBR of 300+ and I want to be able to *confidently* & consistently shoot well at 400 (or maybe 425 or 450 even), using Kentucky doping. This rifle is NOT for general woodsy or mixed-terrain low- and mid-altitude hunting, and not for larger game, elk+. I have other rifles for that. Just wide-open plains/desert, AND mostly-above-treeline.

But also, for spits and giggles, I want this rifle so accurate at 600+ that I could hang in toward the bottom of an F class match and/or practical shoot... not win or place high, but *with appropriately-developed skill & ammo* mind you, just hang in without a DQ or lowest score ever obtained in the history of those comps by a mile. I'm OK with lowest score ever obtained, just not "by a mile". :) So I want the heat dissipation & stringing-resistance that a pencil-bbl won't give me. The bonus is not having to spend all day at the range for load development, waiting for it to cool between shots. See what I'm after here?

In truth, if I build this, it will replace two current rifles: an ultralight in .280 rem with 22.25" bbl (the high alpine rifle), and a heavy custom in .280 AI with a 23.5" bbl (the plains/desert rifle). I want the external ballistic performance of the 2nd one, with the weight of the first one, you see? My thinking is that a 129 Nosler Accubond LR from a 27" bbl in .260 rem will have the same or better external ballistics as the 154 Hornady Interbond from a 23.5" .280 AI (but lighter rifle - so I get my plains / desert rifle in a lighter config), AND have much better external ballistics than the 139 Interbond in .280 rem from 22.25" (but roughly same weight - so I get my high alpine rifle with both better ballistics and less recoil).

And the new rifle would have same or better accuracy than either, I hope, espec. when hot. And could even be potentially used in competition - it will easily make weight, lol.

And the best part is that this allows simplification by replacing two rifles with one - If Gordon Gecko were a hunter with an actual life, too, he would say "Simple ... is GOOOD!"

Simplification might very well make $5 or $6K for such a build worth it.

(Coincidentally, if you're curious, it definitely WILL make it "worth it" if Proof or similar can make my stock I want, which no one has ever made before commercially, with their Lone Wolf or a Manners as a starting point. I have made the stock I want myself, but it took an inordinate amount of time & frustration with my lack of skill and tools. So I don't want to go through that again, and the stock I built won't fit a Rem 700 footprint. It fits a Wby Mk V and isn't overly-aesthetically-pleasing, to put it mildly, lol. Now if Proof or similar will not or cannot, for whatever reason, build the stock I want along with the rest of these requirements I want, then I certainly will not be doing this. But I haven't inquired yet, so I don't know. PM me if you want more info on this).

Taylorce1, do you know - Who makes a commercial custom action which is as light as, or lighter, than the Rem 700 Ti? I need to know whether I need to be scanning for used SA Ti rifles, or not. (Either Rem 700 or Browning A-Bolt perhaps?). Does anyone make a custom Ti action? Or will Proof require that I use the Defiance Rebel? I need to know some weights... Are you saying that the Rem 700 Ti is 2 oz lighter than the lightest one you know of with that footprint? I'm not sure 2 oz is enough to worry about. 4 oz would be, but not 2, I don't think. Oh, and having it come in under 7 lbs or right at 7.0 lbs bare is ok, I've decided, based on your input. I'd much prefer 6.5 or less, obviously, and I will not do it if it's even 7.1 bare (I will come off of 27" down to 26 or less if need be to obtain 7.0 or less). Gotta draw the line somewhere and it may as well be at 7.0. BUT - if the two oz. save from a Rem 700 Ti is the difference between 7.1 and 6.9 bare and still keep the 27" bbl, then that just may be the thing I have to do then!

P.S. I suspect that the scope for this rifle will be the Accupoint 3-9x40mm, but I'm still open to ideas. Possibly the Accupoint 5-20x50. I wish there was an Accupoint in 4-16x44 or similar - that would be the shiznizzle for this build.
 
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Let me suggest that you contact Lex Webernick of Rifles, Inc. and discuss what you need. He specializes in ultra light rifles and I know from personal experience that he does great work.
 
I can only speak on my experience with Mr Webernick. I needed work on my Ruger 77V. The barrel was shot out (throat was burned out from my 220 Swift), and I wanted a new barrel. Since I was tired of dragging around that heavy barreled rifle, I wanted a lighter barrel but didn't want to give up the superb accuracy I had grown used to. There was a gunsmith between my house and where I worked, and it turned out to be Mr Webernick, who I'd never heard of at the time. I went into his shop and he had some amazingly lightweight rifles. I'd never seen anything like that before. I brought my rifle by some days later and asked him to square everything up, make my trigger great, and rebarrel it with something light and "make it a real shooter". He put a 21 inch #2 Douglas barrel on it and did the other stuff I asked and brother...did he make it shoot. The best group was 5 rounds you could cover with a dime. Yessiree, that'll do just fine.

I see you've decided on the 260, and I think that's a fine idea. What I'm wondering though is why you really want that long barrel. You say it's so you can wring every fps and ounce of energy you can get from the cartridge, but is that really necessary? As long as you intimately know the ballistics of the cartridge in your personal rifle, you can adjust for range with the scope. Another 100 fps or so from 4 inches more barrel, to me, isn't good justification for that longer barrel. If your need is for speed, then give up on the short action and go with a 6.5-06 made by a custom guy like Webernick. Having a long action isn't gonna give you warts or cause you significant weight or accuracy problems. To me, a long action is a non-issue in a hunting rifle. But that is just my personal opinion.

I am interested in hearing what you do eventually go with.
 
The Proof/ABS method & materials of CF-wrapping is "asserted" to be superior to the Christensen method (for the same or less $$, to boot). The dual/interlaced CF-based materials dissipates heat better. Christensens are ok, but Proof definitely better, say many in the know. See, e.g., SnipersHide, 24HourCampfire, LongRangeHunting, etc.
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Fixed it for you. I've been a member of SH for years and have read the threads. Most are by people invested in a Proof system. There are a scant few direct comparisons done by third parties, and those have mixed reviews at best. I want the best too and I have shot a Proof and a Christiansen, and I have both firearms and composite design time under my belt. A shorter, stiffer well conceived profile barrel will be no worse, and probably better for accuracy, it will certainly last longer. A gain twist Bartlein has more proven benefit for your pursuit. But yes, you have to make the choice.

A lot of weight can be saved in a skeleton stock made of composites too...
 
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