Why is the .270 Winchester so under loaded?

[Lou270]

Several published loads list 270 velocity with 150s 3000fps+ out of 24” barrels. Federal used to offer a high energy 150gr bullet load at 3000 fps. Hornady does have a 140 load at 3100 fps and 130 and 3200 fps which are up there with top manual handloads

Lou

 

[Koda_]

I just saw the factory .308 150gr Superfremonace load from Hornady is being loaded for 3000fps.

If this is the case how come the .270 Win couldn’t be loaded for 150gr for let’s say 3200fps.

It just seems that manufacturers aren’t utilizing the .270 Win for its full potential. Thoughts?

Not a realistic comparison between two different bore diameters. Comparing with a smaller bore diameter youd have to reduce bullet weight by some percentage.
If you compare the 270, 130gn Superformance to the 308, 150gn Superformance (both factory Hornady rounds) the two calibers are nearly identical in energy with the 270 leading significantly in velocity.

270 Win 130 gr. CX™ Superformance® - Hornady Manufacturing, Inc

Increase your rifle's performance up to 200 fps without extra chamber pressure, recoil, muzzle blast, temperature sensitivity, fouling, or loss of accuracy.

www.hornady.com

 

[35WhelenAI]

The finer points get lost in this day and age. Expansion ratio is what this is about. A larger bullet vacates a much larger area for a given amount of travel down the bore. Pressure falls off with slower powders as the bullet moves down the bore and can never reach a useable peak. Therefore powder gases need to expand quicker in order to fill the void behind the bullet. Larger bore cartridges, all else equal, use faster burning powders than the smaller bores based on the same case.

I can push a 200 gr TTSX from a 35 Whelen or Whelen AI (necked up 30-06 case for those that may not know) just over 3000 fps with data extrapolated from KNOWN published loads, over 2900 FPS with a 225 gr bullet (Sierra data) and over 2700 fps with 250's using Speer data. Can't get near that from a 30-06 with 200's by ANY stretch, without wearing a rifle bolt as a face piercing, and maybe not even then.

I'm very surprised that moderators don't come in and temper the crazy ass speeds posted here. It's bad policy. Every other forum I've been part of wants to cover their base before somebody blows up their face with something stupid gleaned from their forum.

 

[Wrench]

Take a 150/308 and a 150/270 on a long windy ride and see how the 308 plays out....

 

[35WhelenAI]

Take a 150/308 and a 150/270 on a long windy ride and see how the 308 plays out....

I'm not taking that as the point being made here. The point is you can't load a .270 and a .308 with the same bullet weights to the same speed. Ballistics don't lie with respect to longer range, but neither does pressure with regards to the initial post.

 

[83cj-7]

Max based on book loads or max based on your load development? Max load in a traditional .270 Win (1-10") is on the low end of 2800 fps for a 160 gr bullet. No way pushing a 165 gr ABLR over 200 fps faster with 1" more bbl length is near safe pressure in a faster twist bbl.

I'll stand corrected with the published load data backing it up.

That’s the real question. Every rifle is different and mine happens to be throated quite long. The ability to seat bullets much longer essentially creates more powder capacity in the case. Some of my brass is on the 6th firing and I haven’t lost a primer pocket of had to FL size yet.
I know it beats most 280 loads because I’ve had two custom 280s and never got this kind of speed.

 

[seand]

That’s the real question. Every rifle is different and mine happens to be throated quite long. The ability to seat bullets much longer essentially creates more powder capacity in the case. Some of my brass is on the 6th firing and I haven’t lost a primer pocket of had to FL size yet.
I know it beats most 280 loads because I’ve had two custom 280s and never got this kind of speed.

You are loading to approx 270 weatherby velocities in a 270 Winchester with a “long throat”. Seating bullets out isn’t gaining you 15+gr of case capacity.

You are over certainly over 65ksi.

 

[S-3 ranch]

61.5 gr of 4831 & 130gr bullets is absolute max @3160 my M70 270 will do
before the rubber mallet comes out to open the bolt
55 gr of 4350 is max 150gr ?
y’all gonna blow a eye out with witchdoctor recommendations imo
i see nothing wrong with bumping a ladder load up from a manual, but expect some problems if you don’t stop @ pressure signs

 

[TaperPin]

I’m still new to this btw.

Pressures, and what constitutes over pressures are common debates, so while learning about it keep in mind that in strong modern actions the weak point is the brass and to a lessor degree the primers. Pressure standards are set to protect the brass and prevent it from rupturing or jamming up a rifle with a stuck bolt. Pierced primers can also shed metal and push it back into the firing pin jamming up the works, although a good fit between firing pin and the hole essentially takes care of that.

Brass is not all created equal - the brass alloy and hardness from work hardening in the manufacturing process is different between manufacturers - some is softer, some is thicker, some is sort of hard and Lapua is up at the top end of hardness.

Hard brass handles pressures better than soft brass - industry standards are set to what soft brass can handle. Pressure signs can be short case life before case head separation, loose primer pocket from a case head that has expanded too much, case head expansion, or heavy bolt lift from a case deforming so much it can’t spring back.

If a case lasts through many reloads, say 10, many think of that as an allowable pressure for that load in that rifle - that point may be under or over published max loads, and under or over max load velocities. Every gun is a little different.

 

[BCsteve]

Simple reason, its a older cartridge. With a ton of old rifles with lower quality metal. For safety sake and lawsuits. They use lower pressure loads

Sent from my SM-G986W using Tapatalk

Not the reason at all. The .270 Win is loaded to 65K PSI, and has been from the get go. Thats the max that SAAMI allowes for any cartridge.

And back to the OP, Hornady Superformance line uses powders and techniques not available to the average handloader to get that extra velocity.

 

[t_carlson]

As many have said, .270 loads are at max.

In general though it's hard to sell new rounds if you upgrade the old ones. These companies are under loading the old stuff and loading their new cartridges to the gills. Look at what the 30-06 and 7mm RM are getting these days with the newer powders.

The 30-06 is loaded to lower pressures because there are a lot of old military rifles out there with weaker metal and actions.

The 7mm Rem is loaded to lower pressures because when the throat starts to erode, pressure spikes develop for some reason unknown to me.

They are not downloading the .270 to sell newer cartridges. Velocity isn't even king anymore. Its all about high-BC bullets and match-style chamber dimensions.

 

[bdan68]

I'm getting just under 3200 fps with 140 grain bullets using RL26 in my 270, and it has a 22 inch barrel.

 

[DangerRanger]

Several published loads list 270 velocity with 150s 3000fps+ out of 24” barrels. Federal used to offer a high energy 150gr bullet load at 3000 fps. Hornady does have a 140 load at 3100 fps and 130 and 3200 fps which are up there with top manual handloads

Lou

Right But op wants 3200 from a 150

 

[TaperPin]

I had to laugh - the least liked cartridges have to be the 270 and 30-06. These are always well represented on the used gun rack, for quite good prices.

 

[35WhelenAI]

That’s the real question. Every rifle is different and mine happens to be throated quite long. The ability to seat bullets much longer essentially creates more powder capacity in the case. Some of my brass is on the 6th firing and I haven’t lost a primer pocket of had to FL size yet.
I know it beats most 280 loads because I’ve had two custom 280s and never got this kind of speed.

Thanks for those pieces of information. Those are the thingsI hope others are paying attention to and is a different thing than a "stock" chamber/throat that I suspect most guys posting blazing speeds are working with.

I have a 300 Win Mag with a long throat after I fire lapped it. I wasn't planning on it, but ended up I could seat a Barnes 180XBT (boattail vesion of the original X, ages ago) to an overall cartridge length of 3.600 inches. Shortened the bolt stop, added a magnum length follower and drilled out the sheet metal filler at the front of the magazine box in my M70 SM Classic.

Worked up the charge a good few grains over the previous load with the added case capacity from the long seated bullet. 3070 fps with that bullet from a 26" bbl and IMR 7828 is wicked on elk and anything else it was pointed at.

 

[jfk69]

I had to laugh - the least liked cartridges have to be the 270 and 30-06. These are always well represented on the used gun rack, for quite good prices.

I’d say it’s more likely that they are two of the most popular cartridges ever produced here, and so you see them on the racks just because of sheer numbers.

 

[TaperPin]

I’d say it’s more likely that they are two of the most popular cartridges ever produced here, and so you see them on the racks just because of sheer numbers.

I agree they have been the bread and butter of hunters for generations.
However, they are not hot sellers even If they are $50 cheaper than a 6.5 creed.
In the last year I’ve picked up a used 270 and two 30-06s - it’s quite hard to pass up good deals. Maybe a sickness?!

 

[jfk69]

Nope, not at all. I’d take either over a 6.5 Queefmore or any other flavor of the month lol. But I also still like rifles built on M98 Mauser actions, blue and walnut and I don’t care if my camo doesn’t match when I occasionally wear it.

 

[z987k]

Nope, not at all. I’d take either over a 6.5 Queefmore or any other flavor of the month lol. But I also still like rifles built on M98 Mauser actions, blue and walnut and I don’t care if my camo doesn’t match when I occasionally wear it.

I like a 270 as much as anyone, but the 6.5cm has been out for 17 years and is the #1 selling caliber. In 30 years it'll be on racks like the 270s are from sheer ridiculous volume of guns chambered for it. And there will be whatever social media is relevant asking if grandpa's 6.5creedmore is still relevant today.

Given that gun sales are orders of magnitude higher than they ever were in the last century, I'd not be surprised if there's more 6.5cm chambered rifles in existence than 270s already.

 

[35WhelenAI]

I like a 270 as much as anyone, but the 6.5cm has been out for 17 years and is the #1 selling caliber. In 30 years it'll be on racks like the 270s are from sheer ridiculous volume of guns chambered for it. And there will be whatever social media is relevant asking if grandpa's 6.5creedmore is still relevant today.

Given that gun sales are orders of magnitude higher than they ever were in the last century, I'd not be surprised if there's more 6.5cm chambered rifles in existence than 270s already.

Lol, 270 Win has been out for 100 years, nice thought though. However, show some numbers and I'll recant.