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[fuzzybear]

My new rifles is going to be ready next week.

Loading for this one is going to be a new experience for me.
It's a 270wsm, Remington 700 action with a 29" barrel. The manual recommendations for powder charges are all out of 24" barrels.

I usually start 3 to 4 grs less than average maximum load out of three or four different manuals and work up from there.

I'm thinking that with the longer barrel (5"longer) the slower powders would be the best choices, (Re 25, H1000, etc...), because I can get denser loads, more powder, 95% or higher.

My question is.
Will the long barrel, 29", develop higher pressure than the standard 24" length?

[Captain_Obvious]

I don't know, I like 24-26 for rifles chambered for magnum calibers, and 22-24 inches for rifles chambered for ''standard'' calibers. 24-26 produces excellent velocity and accuracy for the fast shooting mags. Some of them do better with a 26 than a 24, like the 270 Weatherby Magnum, I don't know why, since a 7mm Rem. Mag can shoot just as fast and does almost as well with a 24 inch barrel.

[fuzzybear]

Sierra, Nosler and Hornady are making some very good bullets for the .277 inch rounds nowadays. The 308's, 7mm's and 264's have some serious competition with these new .277 inchers

The plan with this long barrel 270wsm is to get a bit more velocity out of a .277 inch bullet along with improved accuracy from the short case.

I like the .277 inch for those windy days when I'm out after prairie dogs and such.

I also like planting myself up on high ground in areas that I know have game that pass through within 400 or 500 yards. I want you to know that I never have and would never attempt a shot on elk at these ranges.

The local gun club that I belong to has two long shooting ranges set up. One ranges from 100yds to 500 meters. The other ranges from 500yds to 1000yds.

These shooters around here get into some very serious rifles. We've got a dozen or so 1000 yard shooters that compete at monthly tournaments. Two of these guys travel all over the country to shoot competition. One of them currently holds the record for 1000 yds. 10 shot group of 3.5" @ 1000 yds. That's some serious shooting. The round he used was a 6.5mm/284 throwing 140gr. target bullet BC.700+ through a custom 30" barrel.

This is going to be fun setting up this rifle. I've got 2 scopes for it. One is a 3x-9x for hunting. The other is a 6x-18x for targets and small things a long ways away.

This rifle, if it shoots, should push a 140gr accubond BC .496 in excess of 3400 fps. with a retained energy in excess of 1800 ft/lbs @ 500 yds. With LESS THAN a 1/2" moa. That is a whole bunch of .277 inch bullet. With a good hold and windage considerations it's going to be a tack driver.

[ChesterGolf]

I think some of the slower burning powders will be the ticket. As for pressure, there should not be much difference because of barrel length. The pressure spike is just as the bullet is released from the casing and this should happen at the same pressure with any length barrel. The only thing you should see is an increase in velocity if the slow burning powders are used. As always if you work your loads up watching for signs of pressure it will be fine.

[fuzzybear]

Thanks Chester

I've got all the components ready to go. Just need to get the metal back. Set it in the stock, seat the bullets for cartridge oal and start loading.

[fuzzybear]

I'm loading and shooting this long barreled 270wsm tack driver. Was over at the gunsmith's that built it for me, this morning, to let him know how well it shoots and have some fine tuning done on it. He shoots the same round in a standard stainless sporter, so we got into a discussion about the new rifles capabilities. I mentioned that I haven't cronographed any loads out of it as yet, so I don't have a clue as to how fast it's throwing these bullets. His response was. It's doing better than weatherby's 270.

The barrel is 3" longer than the weatherby. The rifle oal is 1-1/2" longer than the weatherby. The case is .550 shorter, .024 fatter and uses around 6.0gr less of powder. By his estimates, the bullets are spitting out of the barrel about 150 to 200 fps faster than the weatherby and it's shooting three round one hole groups. Or as he says, a hole the size of a dime. This whole project didn't cost as much as buying a good, quality sporting rifle over the counter. Granted it isn't built to carry around in the woods, but it'll take care of anything in open country. And, the recoil is around 22 ft/lbs. No wizzbang muzzle braked, over blown unneccessarily long, heavy, uncomfortable to shoot rounds for me thank you. There are better ways to get perfomance than buying something that hurts to shoot.

I'm pleased as punch.

[Captain_Obvious]

You should be proud, you have a fine new toy. A 270 WSM shoots fast, I've read some of your listings for it and they're good. A 270 Weatherby Magnum is more potent, though. It's bigger, for one thing, and it loads hotter, in both factory loaded ammo, and in handloads. It's designed specifically for long range authority when hunting game like mule deer and elk. It also produces more recoil than a 270 WSM. I had the privelege this week of doing some target shooting with one of these brutes, and it was an interesting experience to say the least. It clocks 3400+ fps with 140 grain bullets and gets over 3300 with 150s. I'm not sure exactly what the energies are that complement these velocities, but I imagine they are 3500-3600 ft-lb realm, maybe a bit more. Of course, if you don't reload, shooting one of these guys on a regular basis is just going to kill your wallet, as the average cost of ammo is over $30, and for some, about $60. Another issue is rifle availability. You can find a number of rifles chambered for the 270 WSM, you can even get them at Wal-Mart. The least expensive rifle I know of that you can get chambered for 270 Weatherby Magnum is the Ruger Number 1, single shot. I looked into getting one for a long time until it occured to me that I could outperform it with my 7mm Remington Magnum, which not only gets the same velocities and ballistics with the 140-150 grain projectiles, but gets great velocities with bullet weights that aren't generally fired out of .277 caliber bores, the 160s and up in handloads. So as far as the two 270 mags go, while there are distinct advantages to owning a 270 WSM, easier to get rifles and ammo, cheaper, less kick and muzzle blast, lighter weight, typically shorter guns, the notion of it outperforming a 270 Weatherby Magnum just isn't reality. In a neck-to-neck comparison, the Weatherby 270 is more cartridge, period.

[fuzzybear]

The 270 wea is more potent than the 270 wsm. The exception with this 270 wsm I've got is the 29" barrel. With the long barrel I will be turning out more velocity than the weatherby with their stock 26" barrel, and the over all length of the whole rifle is only about an inch and a half longer. Barrel 3" longer, gun 1-1/2" longer. 22 ft/lbs of recoil

[Captain_Obvious]

You listed 3300 for a 150 grain and 3400 for a 140 grain. Those are achievable in a 270 WBY with a 26 inch barrel. Send one off and have it rebarreled to 29 inches and it will shoot much faster. I could have any one of my rifles worked over by Kenny Jarrett or a similar custom gunmaker and have it shooting groups the size of a dime at 100 yards or more. The 300 Jarrett, which is like a 300 WBY, it shoots groups like that, I know this because a friend of mine's uncle has used one for years. He also makes a 7mm-08 Improved, 284 Jarrett Improved, and a long list of others, plus, if you don't want a new chambering, you can just have your gun rebarreled, maybe have a new stock put on, trigger modification, whatever. I've thought many a times about picking up another 7mm Remington Magnum, like a BDL SS or one of the others like it, and sending it off to him to have it modified.

[fuzzybear]

The velocity I stated are conservative estimates. With a 24" barrel the 270wsm throws 130's @ 3300, 140's @ 3200, 150's @ 3100. I was told to conservatively add 35 to 50 fps per inch of barrel. 5" equals 175 to 250 fps conservatively. 29" barrel, 130's @ 3550, 140's @ 3450, 150's @ 3350 conservatively.

I'm not comparing the 270wsm to the 270 wea. I was simply stating that this rig, with the short fat round, will be able to throw a bullet as well as the 270 wea. With less recoil and only an inch and a half more in over all rifle length. Rather than a long round. A short round and a long barrel will accomplish the same thing, with less powder usage, with a rifle that is the same overall length as the weatherby. And, the longer barrel will give the bullet more stability.

[Captain_Obvious]

I don't know, 3550 seems a bit high, but there's really only one way to find out, and that's to test. I have a feeling you're going to eat that barrel up in less than 2000 shots. The 270 Weatherby has drawn criticism in this regard. For whatever reason, the 7mm Remington Magnum is supposed to have better barrel life, even with the same velocities, I don't know if that's true or not. The 264 Win. Mag is another one that supposedly has a shorter barrel life, although I think its a bunch of malarchy spread around by advocates of the 7mm Mag. I don't like light bullets in my 7mm Mag, I hate the accuracy deviation that accompanies them in high-velocity loads. 150 grains is usually my self-imposed minimum. Same with my 30-06. Smaller bullets used in these cases just aren't worth the wear and tear they can create. I can't imagine what a 140 grain bullet frm a 7mm STW does to the barrel, especially in terms of throat wear, it must happen very quickly.

[fuzzybear]

The 264 wm is one of my favorite rounds. I'd have one myself if it wasn't for the belted cases. The thing that hurt the 264 wm was bad press and the introduction of the 7mm rem mag with it's capability to throw bigger bullets. Which made it a better all around cartridge for the one gun hunter.

Wear at the crown is a major culprit to barrel wear. Another is not taking proper care after use and during storage. I was told by two different competent gun smiths that barrels don't wear out they rust out. Tiny little spots of rust, not visible to the eye, form inside the barrel and corrode the bore. The bullets are shot threw these rust spots and drag the rust down the barrel scratching the bore. Another is putting the gun in the case before it cools down. Condensation forms, which forms rust.

It's not a good idea to shoot any barrel at maximum pressure constantly. But, it's nice to know it can be there if you want. If I have the capability to throw a 130gr bullet @ 3550 that doesn't mean that I have to. If I reduce the charge just a bit. I'll still get very good velocity without running at max pressure.

The most important point I'm trying to stress is. Long wizzbang cartridges aren't neccessary to achieve max performance. As an example. The weatherby's are long rifles with long cases. If you get a rifle with a short action that shoots a short fat round and lengthen the barrel so the length of the gun is the same length as the weatherby. You can have a rig that will perform as well as the weatherby. This would be true with the 270 and the 7mm in the new short mags. I haven't done any figures with the 300 as yet.

These new short mags are very versatile rounds. Rifles with short barrels for light weight mountain use to heavy long hard hitters can be designed around them.

[Captain_Obvious]

Did you know also that to some extent, the 7mm Rem Mag and 300 Win Mag ARE short mags? Previously, the 300 H&H set the standard. That requires a longer chamber. Made more sense to have magnums that fit 30-06 length chambers. I don't know if that was the case with the 264 WM, in fact, to me, the 7mm Mag is merely an extension of it, a round that picks up where the 264 leaves off, and goes on up to the heavy-for caliber stuff. Nonetheless, the 7mm Rem Mag, if properly loaded, will throw 160 grain bullets as fast as the 264 can throw 140s.

Proper bore care is essential. Copper fouling kills accuracy, and powder fouling corrodes the bore. How a rifle is stored plays a major role, I store all of mine if a vault with a dehumidifying device inside. I try to oil lightly, excess oil can get messy later on. I also scrub the heck out of my rifles' barrels to remove all visible evidence of fouling and then some.


With the 7mm and 300 Short Mags, you're going to run into a problem: bullet weight. You'll be ok until you get over 160 grains for the 7 WSM and over 180 in the 300. After that, your bullets really cut into your powder column.

[Tankgunner]

Check out this site:

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

This site hosts some of the nation's best shooters. You want the advise of the Palma and Long Range shooters. These events are shot at 800 - 1000 yards mostly with iron sights.

It's a must that bullets remain supersonic out to the target. When a bullet slows to trans-sonic speed it begins to destabilize and yaw decreasing accuracy.

To ensure this velocity at range, these shooters shoot 30 - 32 inch barrels with slow powders. They have a wealth of experience and are willing to share it.


Lee

[fuzzybear]

I've found some good slow powder loads for the 30" barreled 270wsm.
I got a deal on some Winchester Magnum Rifle powder. It looks like this may be the powder of choice for 130's and 140's.