How much over?

[lefty315]

First let me say I've been reloading for more than a few years. I'm always cautious about trying not to get too hot. I figure if I need more speed then I should buy a different rifle chambered in something else. But I do believe I should be able to hit a target velocity for a given cartridge, example being 2700 fps from a .30-06 and 180 grain bullet.

I've had a few rifles over the years where I've been several grains over the book max just to get close to the targeted velocity. I just started loading the 150 LRAB in my Winchester .280 Rem. I think I should be able to attain 2900 fps with IMR 4350. I've been able to do this but I'm 2.5 grains over book. It does look like the bearing surface is noticeably less than other 150 grain bullets so I assume less surface means less pressure= less velocity. Bolt lift is fine, primers were looked at with a magnifier and don't really look much different than 2 grains lower.

I also realize bore and chamber dimensions play into it too. I'm just curious how many others have had to go higher.

 

[Oldtrader3]

Yes, on the .280 specifically. The loading manuals are lawyered down for that cartridge in particular because it was marketed originally for a semi auto and not a bolt action.

 

[DrMike]

In my own loading of the .280, when using the 150 grain ABLR, I got greater velocity w/o pressure signs, leading me to believe the bullet may indeed permit higher loadings.

 

[SJB358]

Same here Lefty, as with all of our rifles and cartridges, the chambers, barrels and even the cases we use are different, so going over book max's don't overly concern me, as long as I am coming at them from below. I have seen the same thing with the Nosler ABLR, seems to run pretty fast for me, at least the 150 in my 270WSM and the 168 in my 7mm WSM.

 

[sask boy]

Thanks guys :wink: I really find these conversations very interesting as I am have always backed off going over the book max. I am going to keep trying & just be careful once going over the max. todate I have not seen a lot of pressure signs.

Blessings,
Dan

 

[longwinters]

I've usually heard that book velocities typically are high for the given loads. And my very limited experience with the chrony would bare that out.

Though I have had very good success with 140 Accubonds and 58 gns H4831.

Long

 

[longrangehunter]

Velocity is a direct relationship to pressure, as long as you're within the expected velocity levels you're more then likely safe even when over the max load listed in the books. And yes the 280 is under loaded in most but not all books.

 

[RiverRider]

I figure that a charge that's safe in a .270 shooting a 140 should be just about safe for a 150 in the .280 based on sectional density (it's close but not an exact match) but I have always subtracted about a half grain just to have a little extra cushion. Since I use QL now, I do things a little differently by equating velocity to pressure.

 

[ScreaminEagle]

Yes, on the .280 specifically. The loading manuals are lawyered down for that cartridge in particular because it was marketed originally for a semi auto and not a bolt action.

Same here. 280!

 

[truck driver]

I'm still using reloading manuals printed in the 1970's for a lot of my reloading and also have some newer manuals to compare to and most of my loads though not over max in the old manuals are over max in the newer ones.

 

[Wis65x55]

I know that it has been stated that the 280 Remington was watered down because the Remington 740 could not handle the pressure. How is this possible when the Remington 740 was also chambered in the .308 which has a max sammi pressure of 65,000 a full 5,000 psi higher than the 280 Rem?
Keith

 

[RiverRider]

I think that old saw is just wrong. I've never heard a watertight explanation as to why Remington hamstrung the .280 like they did, other than a decision to offer a cartridge that would do what the .270 does---only at lower pressure. I have a hard time understanding why any gun buyer would give a tinker's damn what the pressure is, when so darned few have any idea what it even means to begin with.

If Remington knew five years in advance they were going to offer the 7 Rem Mag, maybe they figured keeping a maximum performance spread between the two would help them to market both. They've screwed up countless introductions, so who knows.

I'd like to have been a fly on the wall during their meetings back in those days.

 

[SJB358]

I figure that a charge that's safe in a .270 shooting a 140 should be just about safe for a 150 in the .280 based on sectional density (it's close but not an exact match) but I have always subtracted about a half grain just to have a little extra cushion. Since I use QL now, I do things a little differently by equating velocity to pressure.

RR, I run the same as you, within reason, QL is a game changer, along with a chronograph, especially when you figure in H20 capacity..

 

[lefty315]

I've run my 7x57 in a Ruger No 1 up to 280 velocities with no issues. That's one cartridge that is severely under loaded, I just wouldn't think the 280 would have been listed so. I just traded off a Browning x bolt in 280 for this Winchester. Just thought it odd that both rifles needed to go over a couple of grains to get close to where they should be. I've never shot any factory loads out of either but I'd be curious to chronograph some.

 

[Oldtrader3]

I am going by what Mike Walker said after he retired from Remington. The .280 was stretched .050 longer but no load adjustment was made because it was released in the Model 760! Mr. Walker ought to know!

Additionally I owned a .280 Remington for 17 years and my grandson has it now. For years, the book max on 140 Partitions for the .280 Rem, was 44 grains of IMR 4350. Well I never could get more than about 2740 fps with that load. Finally I slowly worked up to 58 grains, IMR4350, 4 grains over book, and my groups shrank to sub MOA and my velocity went up to 2950 fps with the 140 Partition.

 

[lefty315]

Thanks for all the input. Have a Merry Christmas everyone!!!

 

[Horsethief]

24" barrel, bolt action 280 Rem, lg rifle primers and I know some of these loads are hot, but there were no pressure signs AND they're all sub MOA @ 100yds. The Superformance load made the smallest group.

140gn Game King, 55gn H-4350, 2962fps
150gn Game King, 58gn Superformance, 3042fps
150gn Game King, 58gn H-4831, 2965fps
160gn Partition, 58gn RL-19, 2975 fps

 

[Mountain Goat]

I love the 280 Remington! My first was a Browning A-Bolt composite stalker, 22" barrel and a Timney trigger spring kit. The only manual I had at the time was Speer #13? The 145gr BTSP with a book max load of IMR4831 gave me exactly what the manual said it would, 2950fps. My step-son shot a lot of animals with that load!

In comparing 280 loads to 270 loads, it makes no sense to me why a 270 can take more of the same powder than a 280 with the same bullet weight. Sure, chamber, barrel, free-bore, etc. but that can't always favor the 270 acroos the board. But, then again, why does a 120gr .264" have a higher BC than a 120gr .257" of the same bullet? It must be that bullet maker magic we often read about.

 

[Elkman]

The dumbing down of the .280 was one of the reasons that never took off like it predessor the .270. Winchester did the opposite, crammed the 270, up with pressure, and published velocities out of this world. O'Connor fawned over it around the world and Keith, steamed and fussed. Just some history as "I" remember it.

 

[Wincheringen]

I vote for accuracy over velocity. All the talk about 50 FPS isn't worth anything, deer and paper just don't know the difference. Find an accurate load and go ventilate some critters. My particular .280 happens to be finicky and likes bullets snugged up to the lands. Not going hog wild for velocity increases case life and decreases recoil. Components aren't getting any cheaper, so I don't waste them.