I am still screwing with the lack of accuracy between the Nosler 150 loads and the Hornaday 140 BTSP.

Noslers usually touch to 3/4 inch groups at 100 yards depending on how I am shooting. I Use 57.5 H4831 for the loads.

For the Hornady I have tired 55 thru 60 grains H4831 for the workup for both.

The big difference between the bullets is the seating depth. Noslers are seated close to the lans and the Hornadays are seated to the crimp/cannelure line.

It is hard to jack with the seating depth since the Hornadays are more tappered to diameter than the Noslers but I did an approximation and using the back of the crimp line the H 140 moved out .11 and the 130 SST .085 of an inch from the back side of the crimp and if you load to the middle then is it out further.

All the bullets fit in the magazine and cycle thru the rifle.

I am wondering if the bullet jump is too much for the Hornady rounds for accuracy?

Did talk to Hornady and the boxes passed their specs.

Opinions Other than load some and shoot

Jim,
Assume you're talking about your .270W here, right ? Just going by your recent .270W related posts. Sounds like it's a battle finding acceptable accuracy but this shouldn't be impossible with a .270W as it's usually inherently accurate, unless your rifle is junk. The bullets you're using generally shoot well also. Re seating depth there is usually a sweet spot where your rifle will consistently produce it's best accuracy, and each bullet type will have it's own sweet spot, but a bit of prior work is necessary before experimenting to find the ideal seating depth. H4831sc is a good powder choice and it sounds like you're on the right track shooting a spread of charges, testing for accuracy and pressures etc. If H4831sc has potential, somewhere among those charges should be one that produces a "best" group. If that doesn't happen you might have to change to another powder and recommence the process. Anyway, the "best" group should indicate the ideal charge is near. Make more loads .3 and .4 grains both higher and lower than the "best" group load and shoot those. Again, one of those should produce a best and most accurate group. If accuracy is good enough you might want to settle on that COAL. But you can fiddle with COAL looking for the absolute best accuracy. Berger Bullets produced a guideline some years ago ( I don't shoot Bergers ) I follow when doing this myself.
1). 0.010" off the lands
2). 0.050" off the lands
3). 0.090" off the lands
4). 0.013" off the land
One of these should shoot much better than the rest.
Hopefully if it all works out getting to this point the loaded rounds still fit the magazine. Once or twice I've seen guys with long throated rifles and long loads that shot brilliantly but had to be single shot as rounds were far too long to cycle through the magazine.
Good luck !

My experience is that seating depth does matter and I have had to switch bullet type/weights in order to get a bullet to seat where it needed and still fit in the magazine. The Berger example above is a good one as their target bullets are said to shoot best jammed into the lands but it was discovered that they also hot good seated really deep. Thus the system to find the sweet sport. You can read about it on the Berger website. There is always the possibility that your rifle will not shoot that particular bullet well.

my best luck with Hornady's always seems to come with the cannelure showing just above the case mouth.

There are very many different opinions on this.
Most people believe that it makes a lot of difference. Some believe very small seating depth changes can make a big difference.

Hornady themselves on the basis of a huge amount of testing have stated publicly that in their experience it doesn't make a difference, particularly with their own bullets.
They have a number of podcasts on Youtube where their chief ballistician discusses this. In their own words, change the bullet or the powder, everything else is virtually irrelevant.

My opinion is somewhere between the two extremes but I have not done enough testing to be able to state that my opinion works, but here it is none the less:
A number of tests have indicated that case neck tension does make a significant difference. By inference, the difference must be in how early in the pressure increase the bullet starts moving and how predictably it accelerates.
But the engraving force is significantly higher than the "case release force". Thus, if you want to see whether a bullet and powder combination can be accurate in a given rifle, load the bullets so that they engage the rifling, irrespective of any other considerations, and shoot a few groups. Note that pressures will be higher like this and that (again according to Hornady's extensive testing) best accuracy is not achieved at maximum allowable pressure, and choose a suitable load.

If the above groups are good, the combination deserves further testing and development. if not, change bullet or powder or possibly primer, and try again.

Note that there is a seating depth range where the bullet is in contact with the lands, but removing a loaded round from the chamber will not result in the bullet remaining in the barrel. This range is probably dependent on the caliber and the particular bullet and probably also on the condition of the barrel's throat but is probably somewhere in the region of 0.5-1mm (0.02-0.04"). Note also that if the bullet enters the case by less than one caliber, more care must be taken with the ammunition so as not to push the bullet out of concentricity.

My own method for a hunting rifle.

Seat the bullet to the maximum seating length for that cartridge, if it fits the magazine, and the bullet is at least one caliber in the case.

Lighter bullets I seat one caliber in.

If this does not allow seating in the magazine, I seat deeper so it fits in the magazine.

In my own experience, and shooting both a 308 Winchester and a 222 Remington.

I tried the same load, same bullet.

Seated so deep that the bullet would fall into the case if pushed a bit.

Seated so far out that it touches the lands.

Not much difference in either accuracy or velocity????

Too many variables to be pontifical!

Some bullets your rifle will NOT like. Period. Some powders will not like your bullet. Period. Some bullets will not like either your rifle or powder or primer or seating just so!

My Tikka in 9.3 x 62 is one of the most accurate rifles I've ever owned in over 40 years of making my own handloads. BUT it hates the 270gr Speer!!!! It has rejected it and I'll make NO more attempts to cram it down its throat!

Bob
www.bigbores.ca

In bolt action rifles, as seating depth goes up (shorter OAL) pressure goes down. When trying a new bullet - powder combo I seat to within .010" of the lands as long as this will fit the magazine, and work up to max pressure. I then will try .020, .030, and .040" off the lands with the same load to see if accuracy improves. This way I have a little head room for the pressure and a very accurate load with near max velocity.

I've always seated my bullets 1/8" from touching the lands and gotten great accuracy out of my 270. I shoot Sierra 90g HPBTs at 3400 fps for varmints and 150g Partitions at 3000 fps for bigger stuff.

I have not measured the seat depth except to touch some where on the crimp line and there is a lot of space to the lans. Shooting 55-60 grs H4831 gave no sweet spot for for SST 130 or 140 BTSP

With the Hornaday bullets being shorter than the Nosler bullets I can move the Hornaday bullet's crimp quite a bit out from the end of the shell.

This was my last trick to try. I did notice that the crimp on The Hornaday 140 SP is different than the 140 BTSP in 7mm. I will do a measurement for the distance and go from there.
Thanks, Jim

quote:

Originally posted by .458 Only:
Too many variables to be pontifical!

Some bullets your rifle will NOT like. Period. Some powders will not like your bullet. Period. Some bullets will not like either your rifle or powder or primer or seating just so!

My Tikka in 9.3 x 62 is one of the most accurate rifles I've ever owned in over 40 years of making my own handloads. BUT it hates the 270gr Speer!!!! It has rejected it and I'll make NO more attempts to cram it down its throat!

Bob
www.bigbores.ca

^^^^This is 100% correct.

Guys don't always realize that it takes some serious fiddling around to find the bullet, powder, seating depth combination that THEIR rifle likes best.

You can play around more or less than I do (I play tons since I shoot every week at least once....unless I'm out hunting) but I always have an accuracy goal in mind and, once reached, I verify for at least 3 different days back at the range.

Way too many variable to help you much but you've got to have the tools, training and time to determine how much jump or jam you're really getting. Like Saeed said, this could be limited but the magazine length.

Zeke

Agree fully. I typically find a big game premium bullet that both I like and my rifle likes, work up an accurate load with enough velocity and call it quits.

+1!

Seating the bullet so it is just about touching the lands means that when the primer goes but will just move to the lands and then stop and pressure builds up in the chamber before it moves down the barrel. This gives consistency and thus accuracy.

However a decent crimp on a bullet seated at standard depth will achieve the same. And the extra tension of a crimp will make your ammo much more robust and reliable for hunting.

Seating the bullets long will inevitably mean that sooner later one will get stuck in the lands and when you empty the rifle your cartridge case empties all the powder over the inside of the the action. Then the stag you are after appears and the nearest cleaning rod is down back at the lodge.

With hunting ammo, bullet type, terminal performance and reliability is far more important than that last 1/2” of accuracy.

quote:

Originally posted by chuck375:
I've always seated my bullets 1/8" from touching the lands and gotten great accuracy out of my 270. I shoot Sierra 90g HPBTs at 3400 fps for varmints and 150g Partitions at 3000 fps for bigger stuff.

Chuck, what powder are you using to get 3000fps with the 150gr?

I use Rem brass, fire formed, then I only neck size (but I run the loaded ammo through the action before I hunt with it) CCI magnum rifle primers, 58.5g H4831 and Nosler 150g Partitions. This used to be a max load in the 70s reloading books but they have gotten more conservative over the years. Please work up slowly and look for signs of pressure as each rifle (fast or slow barrels) may reach max before you reach this load. I have been using this load in my late 60s Rem BDL since the early 70s. It also works great in my son's LH BDL 270 also a 22" barrel. Just checked Nosler calls 55g max way underpowered imho. Just found this article from Handloader Magazine which is more in sync with my experience.

https://www.handloadermagazine.com/270-winchester-0