I'm not a fan of a 22 inch barrel on a 280 AI but am curious as to the velocity gain obtained when reaming a 280 Rem to 280 AI in a 22 inch pipe?

I am a fan of 22” barrels on hunting rifles to be carried in rough country. Warren Page’s “Old Betsy” had a 22” barrel and it was chambered for the 7mm Mashburn which is close to a 7/300Win. That said, I have had two different “improved” 280 Remington’s. One was an Ackley and the other an RCBS. Of the two I preferred the RCBS version. I was very interested in the velocity gain so started with new barrels, had reamers made, shot & chronographed both barrels before and after. I also had two other 280’s. Both had long throats for OAL’s of 3.48”. I was trying to maximize a light mountain “sheep rifle”.

I measured case head expansion to track pressures as it was the only way I had to attempt to be objective. I ran the loads over two different chronographs. I expended a lot of time and money. This is what I found.

Most of the velocity gains over the standard 280 were due to higher pressure and increased OAL of the ammo. At equal pressures, the difference was 35-40 fps. I didn’t mention that I started with 24” barrels and then cut both to 22”. The velocity loss with optimal loads either of the improved versions was about 22-25 fps per inch.

So, an improved 280 using optimized loads with 140’s in a 24” barrel will move around 3125, in a 22” the improved will go 3080, and in a standard 280 with a 22” barrel the 140’s move along at 3050. There is some variation in barrels so to minimize that I got three of the barrels from a maker of cut rifled barrels all of which were made sequentially. The barrel maker made test barrels for commercial laboratories and NASA.

I was using 98 Mauser actions and the improved cartridges never cycled from the magazines as well as the standard 280. I had the best metalsmiths in the country try to make them work. There isn’t anyone who can make an improved function as well as the standard 280 using a 98 type action. This isn’t because of the sharper shoulder but because of the lack of taper in the case body.

I had been reading and was convinced that a 280 was slightly better than either a 270 or a 30/06. I loaded ammo for a buddy who had a 270. It wasn’t a big deal to get his 130’s up to 3100 fps in a 22” barrel. Eventually I sold all the 280’s both standard and improved in favor of the 270. About that time I started doing much more hunting and have used a rifle chambered for the old 270 for many many trips. I sold all my 7 and 30 magnums. Today all I use it a 270 and a 375.

If you must have a 280 then increase the throat to 3.48”. The 22” barrel is noticeably more agile to handle and carry.

Wow, you took that task seriously! Thanks for the info. Just curious on the 270, did you twist it faster than 1/10. I ask because I have two of them and they are both .5 MOA guns with 130's but with 150's not so much.

Holy [bleep] RinB. That’s an impressive bit of information.
Thanks for taking the time ...

This has to be one of the most informed and impressive posts I've read since I started internet hunting in 2001.

Thank you for that info. I have a 22" .280 and have thought about getting it reamed to AI. Haven't done it, mostly because I have a 7mm RM and enjoy the .280's mild recoil. It does what I want and will likely stay unchanged as long as I own it. Why mess with a good thing?

Very interesting test.

Did you consider NOT increasing the throat, increasing twist, and increasing bullet weight?

The 270 ain’t so gay after all!!!!

JMC,
I fooled around with different twists in the 280 and the 270.

In the 280, 1-9.5, 1-9. I used 140 and 160 bullets. Initially I thought the 160’s would be better but found the 140’s preferable. In the 270, 1-10, 1-9, and 1-8. I also tried different bore diameters.

Most of this didn’t make any objectively observable difference. I do believe faster twists tend to expand a bullet to a very slightly larger diameter. Here I am talking about monolithic or bonded core bullets.

I have been using a 1-9 twist in my .270’s with an OAL of around 3.48”.

At the same time I was doing similar experiments with the 300Win and decided that it didn’t work much better than a 270. I had several but have sent them to live elsewhere. I have fiddled with many cartridges and decided they are a waste of time if you are interested in hunting.

I began trying to build the optimal mountain rifle and found that I couldn’t improve on the 270 especially when used with modern hunting bullets. A 270 with 130 TTSX will penetrate around 34” of eland meat and bones.

All of my expensive experiments convinced me that there really isn’t much to learn. Go to a 9.3 or a 375 to get to a meaningful difference.

I spent the cost of a pretty nice sports car to learn that there isn’t much to learn. It would have been wiser to spend the time and money practicing and going.

So then what you're saying is that the answer is the 270Ai...?

Did I get that right?

Boog,
Surely you jest! Go back and carefully read my first comments.

RinB, I’ve been here a long time, don’t post much. That’s about the best post I’ve seen on here. Thank you.

JBab,
Thank you, sincerely.
I am always happy to pass along that which I have learned.

Great Post Uncle Rin- I've only had one .280 AI and that was in a 22" Mountain rifle reamed out. I was dealing with R22 then and a finick barrel. The loads it liked ( 150NBT/61gr R22 and 160HC/7828 ( don't remember the charge now, 25 yrs later) were 150/2950 and 160/2800. I only beat my standard 280 loads by 50 fps. It was still alot of fun, but I learned alot from that. Another Ackley Improved I never seemed to get much out of is the 30-06 Improved. My 35 Whelen AI had the stock "Classic 22" factory barrel", but the loads it liked were, come to find out from QuickLoad data, 20 yrs later, all ran in the 72-74K range, ha. I moved on. Now I like my 24" .270Win and 24" 300WM. They scratch all my itches...:)

Excellent work and post.

Better you than me!

RinB thanks for your post and research. I purchased a Rem 700 MR 280 a couple years ago. Before I purchased it, I researched the AI version and decided I didn't need it. My 280 pushes a
150 NBT at 2950.

Deans

Deans,
Your 280 loaded with 150’s is in the group of the very finest of all time. I have used the 150 Swift Scirocco’s and they are great. The 140 TTSX is another great one.

If the 280 was readily available worldwide, I would still be using one. However it isn’t. I abandoned the 280 in favor of the 270 because on one trip I didn’t have time to load ammo and thought I could buy some. I drove across south Idaho and Wyoming stopping in every town looking for 1 box of any 280 ammo and couldn’t find a single box. I would have settled for 5 rounds. Nada.

I used the 280 on around 75 head of plains game. After using the 270 on many more, I can say there isn’t any difference between the 270 & 280. Also, I have used the 7Rem and 300Win. The magnums recoil more and make shot placement more difficult. In what counts they aren’t objectively better.

Regards,
R

J K,
I fiddled with 2 338-06’s and 2 338-06 AI’s. The total “gain” was maybe 25-30 fps; note that is total gain not per inch. Waste of time and resources. Lots of guys want to be different. I suggested getting a tattoo on their forehead saying “DIFFERENT”. Last time I got a lot of grief for my suggestion.

Best to you,
R

Yes...of course...just kidding...

I'm not as clever as some here but I do try my hand at levity from time to time

However, I am in complete agreement with your conclusions.

I put tubes on several rifles for a fellow who finds Elk in places where long range opportunities are frequent, and often the only ones presented. Being a meticulous shooter, and having gone through the gamut of 300, 338 blasters, he found the 270 WSM to be equally effective at extended range with the right bullet with a LOT less blast and shoulder banging. That's since changed somewhat since Matrix got out of 270 business.

The 280 is about as good as it's going to get on the '06 case. I decided long ago that, for the money, the best way to improve any round is to put a better bullet on top.

For a cost of about 2 quarters one can often achieve as much as 50% greater downrange velocity / energy...and what a wealth of bullets are available for the 7mm bore...2nd only to 30 cal.

If one shoots far enough to need it, that is..

I'm still trying to wear out the barrels on the 30s I have.

There was a thread where such a comment would have gotten you called a member of the lace panties brigade. The suggestion was for a new hunter to start out with a 300 mag.

RinB I totally understand going a hunting trip and need to find some ammo. I had a 7 RM and left my ammo at home, I was able to acquire a box at a small town. It was a box 175 gr ammo and my
rifle wasn't sighted in for that weight. Ever since then I make a list of what I want to take and check it off as I put it together.
Thanks for compliment on my choice of bullet weight for my 280.

Deans

Apologies for the hijack, but this article is so good...
https://www.gunsamerica.com/digest/ross-seyfried-busting-the-magnum-myth/

RinB

Speaking of the 270 Win, the 9 twist should work better for the mono's and 150 grain bullets but how does that twist do on 130 bonded or cup and cores? Seems to me that the majority of shooters are shooting heavy for caliber or long for caliber bullets and ditching the 10 twist for a 9 would really help the 'ole 270 and also be a selling point for gun makers. Your thoughts?

I don't get why people outside of short range BR are afraid of tighter twist. I've been shooting 100 grain bullets from an 8" twist 6.5 and they've done great.

If I had things to do over again I could easily get by with a: 22RF, 223, 270-280-30-06, and a 375. I like the 280 AI but realize even a 50 fps advantage over the standard is pushing it. But the reloading data foe the 280 is limiting and once you run it to higher pressures you might as well be in wildcat or other uncharted territory.

New barrel and dies go either way. Reaming out an existing barrel especially if it shoots well is usually not worth it. As has been pointed out before two more inches of barrel will make the velocity difference between the standard and AI almost nil. This is only for the more modern relatively straight tapered cases, some others will show a greater increase.

Next 270 barrel will be a 1 in 8.

M Man,
Completely off topic but I have many great memories involving lace panties. Nuff said.

Boog,
I agree about bullets with one caveat. The super high BC bullets are really great for ranges over 450 yards at least as far as hitting the target is concerned. My concern involves terminal performance. The bullets producing the best terminal performance while pretty good don’t hang with the super high BC in terms of wind drift,

I am primarily a hunter and enjoy getting close. My self imposed range limit is 440 yards. To me the real thrill is getting very close to something that is unaware of my presence. Mentally I am like a bow hunter but just don’t care much for those contraptions.

I'm sure you weren't the I one wearing them though.

Pretty much my conclusion of the diff between .338WM and .340 Wby.

Cheaper to feed the WM, easier to find ammo in some places, and the critters can't tell the difference.

Tejano - I think I understand what you were saying here, but I wanted to be sure.

I think you are saying that a 280AI at SAAMI max pressure of 65Kpsi is about 50fps faster than a 280 at 65Kpsi (5Kpsi over SAAMI max pressure). But then you are into wildcat/uncharted (guessing) territory.

I had a kimber Montana 280 ai and a rem 700 ks 280 at the same time. The rem mag box allowed me to load them out a little longer so they were pretty much equal speed wise. I now have a Christensen ridgeline in 280 ai. If I were building I'd do a standard 280 on a rem action with a 22" rem sporter barrel 8 twist. Might even do a remage.

Bb

This has been an intersting thread to follow. Not to derail the thread, but regarding magazine box length, any idea which factory rifle has the longest? Ruger? Remington? Winchester? Etc?

Rem 700

Thanks, MM.

Leftover angst fom when bullets weren't as well-balanced are they are now maybe.

More folks might try faster twists if the factories offered the option. Most are still cranking out the old standards, and aside from the loonys here and elsewhere, how many are going to invest time and money in a new barrel on their own? I have a 1-7" 6mm and a 1-8" 6.5, but they came that way.

Have to add to the kudos being piled on RinB for his perserverance and also his detailed story about his adventures. I've mostly stayed with a stock .270 since the '80s, and don't lean on it at all; 160s at about 2700 or 130s at 2900 work very well, on paper and Bambi. I'd like one of the 9" FCs, but mostly for the light weight, and with two regular ones, it remains a notion.