loading for a shorter barreled rifle

[steveNChunter]

I recently aquired a Remington 660 in 6mm rem. It has a 20" barrel, 1:9 twist. I will primarily be using it to hunt whitetail deer. I already have another rifle in 6mm rem, a Rem 700 varmint special with a 24" heavy barrel that I load 60 gr hollow points for.

I realize I'm losing a good bit of velocity with the 20" tube, but its such a handy little carry rifle that I dont mind. I want to load at least 80 gr or heavier for it. I like the 80 gr Speer deepcurls but they are too scarce right now. I've also considered the 85 gr partition. I'm not opposed to going as heavy as 100-105 gr if they shoot best in my rifle.

My question is, does a short barrel rifle like different powders and weights than a longer barrel? If so what kind of powder and what bullet weights would be better for the shorter barrel?

I have heard ball powders like Win 760 and similar, and heavier bullets are better for short barreled 6mm's. But I've HEARD alot of things that don't always turn out to be true.

[Mike / Tx]

Your shorter barrel shouldn't be much of an issue to load for. It will probably not shoot the exact same load you use in the other rifle, to the same POA, or possibly not even group as well, but it can use the same powders and bullets very effectively.

I have a Win 70 in .243 that has a 20" barrel on it. I agree the shortness is handy, but it's still long compared to my Ruger Compact .308 at 16.5". I have found only a 250-300fps difference with the Ruger using factory 150gr loads, so your not going to loose much velocity.

With my Winchester, I found most medium burn rate powders work the best overall. My best loads have come using H-4350 under the 95 and 100gr Nosler bullets. The load for the 95gr BT will usually group under 1/2" at 100yds easily if I do my part, and stick within 3/4" at 200. THe 100gr loads are using the now discontinued 100gr Solid Base and will keep to around the same but slightly bigger at 3/4 at 100 and around an inch at 200. Either of them will easily drop a deer or yote.

I would suggest you use what powders you normally use in your other one first, just to see how it is going to pan out. You wouldn't use up a lot of complonents working through a quick ladder test. At least you could work up from start loads to find what your max might be too. I really like to stick to the heavier bullets with the slower powders in mine. Mostly we hunt deer and hog, and the heavier weight helps out. I also use the slower powders simply to try and keep the throats in decent shape longer.

[Bailey Boat]

Give 3031 a try for powder. It's been around longer than dirt and still works...

[Brian Pfleuger]

Generally speaking, the powder that produces the highest velocity in a long barrel will also produce the highest velocity in a shorter barrel.

However, that powder will also produce more and more muzzle blast as the barrel is shortened and will also produce more recoil from "rocket effect" than a faster burning powder might.

Bullet weight usually won't matter within reason. If a bullet would be stable at 24 or unstable at 20, the few fps difference isn't going to dramatically alter its stability. You're probably only losing 200fps at most from a 24" and probably closer to 100. In any case, not enough to really change the stability.

Personally, I like lighter bullets anyway, for speed, and faster powders for reducing muzzle blast and the associated rocket effect recoil.

[GWS]

Remington 600 Mohawk. One of the few rifles I bought when I was young that I still have. Paid $106 new for it in .243. Short barrel, but who cares if its MOA with factory ammo out to 100 yards. I like Winchester 760 in it...very accurate...sub MOA when using 85 grain Sierras. IMR 4350 with 100 to 105 grain bullets is extremely accurate as well.

An 18 year-old grandson of mine borrowed it last fall and got his first big mule deer with a heart shot on his first hunt. (he was using 100 gr. Remington Corelokts). I believe it was a 130 yard shot. Damned smartalec kid.

BTW, I don't believe deer care one way or the other about the slightly lower velocity of shorter barrels. They still have the potential to be accurate as hell.

[wpsdlrg]

20" isn't that short, as compared to the standard 22" or 24". So, a change of powder/ loads may not be necessary. I second the suggestion to try your standard loads first, before deciding that you must change anything.

If your rifle had a seriously short barrel, that would be another story. My current Mauser, which I re-built and re-barreled from the standard military length (23.6" barrel), to a carbine length rifle (17.5" barrel)....would fit into the "another story" category. My standard loads with the full length barrel, (using IMR 4064 powder) produced lots of unburned powder with the new barrel, as well as a significant velocity drop (beyond that which might be indicated). A switch to a faster powder (Hodgdon Benchmark or IMR 3031) solved the issue. New loads had to be worked up, of course, but no change in bullet weights was needed. I should add that the rifling rate on the new barrel is the same as the original.

Heavier bullets "better" for shorter barrels ? I think that idea comes from the concept of trying to maintain equivalent impact energy with longer barrels (i.e., since you lose velocity with a shorter barrel....use a heavier bullet to make up the difference). It's WAY more complicated than that. Thus, this concept is simply a useless generalization.

So, depending on your current load(s), you might not need any change. Or you might need a bit faster powder, if your current powder is quite slow. I have a feeling that this will not be the issue with a small cartridge like the 6mm. On the other hand, I do not know the 6mm Rem. cartridge. But, do test your existing loads first.

[Clark]

Bart Bobbitt, who posts here, came up with a formula for barrel life.
He came up with it earlier, but he posted it 10 years ago on usenet
https://groups.google.com/forum/?hl=...ns/ERNL0-MfjLw

My formula is:
1. Calculate the bore area in square millimeters using bullet diameter.
2. Use one grain of powder for each square millimeter. This is what I call the reference, or bore capacity powder charge. Example: .30 caliber bore, .308-in. (7.82 mm)bullet diameter = 48 square millimeters. Bore capacity powder charge for .30 caliber is then 48 grains. A .30 cal. cartridge that burns 48 grains of powder (.30-06) gives a barrel life of about 3000 rounds of best accuracy.
3. If a larger 30 caliber cartridge is used and it burns more powder, the accuracy life in rounds for that bore size is reduced. The amount of reduction is determined by:
a. Divide the increased charge by the bore capacity, then square the answer.
b. Divide that answer into 3000. Example: A .300 Wby Mag. has a bore capacity of 48 grains. This cartridge burns 91 grains of powder. (91/48) squared is 3.6. 3000 divided by 3.6 is 833 rounds. Three competitive shooters told me their .300 Wby. rifles gave them between 800 and 900 rounds.

Of course a worn out barrel to a national level hi power competitor would not be noticeable to a schmuck like me, pleased with myself when I shoot a deer at 500 yards.

In highpower competition, accurate barrel life ends when shots missing where called by about 1/3rd more than when the barrel was new and in its prime. In other words, when the barrel's grouping ability is about 33% bigger.

[Art Eatman]

I've tagged a couple of dozen bucks with a 19" Sako .243. I got lazy and use the Sierra 85-grain HPBT for deer and coyotes. My load is 37.5 grains of 3031. I consider that max, but as I said, it's .243 and not the 6mm Rem.

I'm picky about my shots, only taking neck shots or cross-body heart/lung shots.

[Sure Shot Mc Gee]

Why not use the same powder you already use in your other 6mm rifle. Probably won't gain anything by using a different powder than what you already have available. Just because you are increasing your bullet weights doesn't suggest to me you need a whole different brand of powder to accommodate that purpose.

S/S

[steveNChunter]

I'm using H335 in my 60 gr loads for the other rifle. I figured it burned too fast for the heavier loads. Am I wrong about that? I realize H335 may not be everyone's idea of a good powder for the 6mm, but its the load my Dad started using for the rifle many years ago and it is so accurate that I refuse to mess with it. I've just been duplicating his old load data he wrote down.

I have a couple pounds of Win 760 on hand, I was thinking of trying it first in this rifle. If the 760 doesn't give good results, I want to try Hybrid 100V. I'd like to get ahold of a box of the 80 gr Speer Deepcurls but nobody has them in stock. If I can't get any of those I'll probably pick up some 85 gr Partitions.

[Sure Shot Mc Gee]

Your right about H-335 Sir. It doesn't seem to be listed in anything I have for use in a 6-mm. But W-760 is. And shows pretty good results in regards to speed. I wonder how your father came to using H335? I know first hand that BLC-2 and H335 are near identical powders in performance and just {maybe} your father knew that too. But I have nothing written in ink on 335 itself. As far as burn speeds H-335 is in the same family of powders such as 30-31- 748. I wouldn't suggest in any way to drop the charge weight as low as you could in a BLC-2 load and use 355 in place of BLC-2. And work it up scale from there to find its sweet spot for the bullet weight intended. No Sir I couldn't recommend that being done. But how ever you proceed I wish you luck.

S/S

[Brian Pfleuger]

I know first hand that BLC-2 and H335 are near identical powders in performance and just {maybe} your father knew that too.

They might be close on "performance" but they're no where near each other on burn rate charts or load data. Hodgdon lists 335 at #81 and BLC2 at #102 and charge weights for identical bullets in cartridges that use both powders are substantially lower for 335 than for BLC2. Between 2.5 and 3.0 grains different in .270Win and 5.0gr difference on 140gr in 7mm-08.

[Sure Shot Mc Gee]

steveNChunter: Apparently the Staff here has added a correction concerning BLC-2 and H-335 as the two powders being widely apart in their burn time. After looking at the burn rate table Hodgdon has up on their site. Perhaps you should go to that site and form your own opinion how you wish to proceed. Your thoughts in using W-760 are indeed correct. That may indeed be the best powder to use since you currently have it on hand. Verses H-335 which apparently isn't a suggested powder to use in the 6-MM Remington that I can find in my material at hand.

S/S