Bullet Seating Question

CoyDog · June 5, 2001, 01:37 PM

I've been loading for my handguns for the past year, and am now starting on rifle reloading. I'm looking at using 130 grain Nosler Partitions for a .270, using H4831 powder.

In determing the best bullet seating depth, I measured the distance to the lands of my rifle. This was very long, compared to .270 factory ammo. If I tried to seat the bullet so it would rest just short of the lands, it would barely be seated in the cartridge neck. The rifle magazine is quite long (Rem 700) and would accomodate such a long cartridge, but I wonder about proper seating.

Is there a rule of thumb about how deep in the neck that a bullet must be seated?
Thanks, CoyDog

45Colt · June 5, 2001, 02:14 PM

Andy, my best advice would be for you to go to the Benchrest site, Benchrest.com. These folks know nearly everything there is to know about bullet seating, etc. In a nutshell, though, you need to make sure that you seat your bullet at least 1/2 caliber into the case. e.g. if you're shooting a .270, it should be seated at least .135 into the case, or more. (Not too deep, though, check the manuals for OAL). Next step is to make sure that your round will fit into the magazine if you're huunting with it, and that it doesn't get battered by recoil when in the mag, and then shift the OAL. That plays hell with consistency of accuracy.
HTH Walt

**Bud Helms** · June 5, 2001, 04:52 PM

Most cartridge designers try for one caliber seating depth. These benchresters, though, routinely seat out to less than that. Be aware that the farther out you seat the bullet, the more fragile the whole bullet-to-cartridge neck interface becomes. Out beyond a half caliber depth, some caliber bullets can be pushed over with finger pressure, depending on neck tension.

Benchresters have been known to use very slight neck tension deliberately, so that on chambering a round, the bullet contacts the rifling and easily slides back into the neck on bolt rotation. A round assembled in this manner can come apart if chambered, not fired, then ejected. So remember, the benchresters need to know what you're going to use the rifle for, if you ask them for advice. Without telling them that, they might give a benchrest answer you may not be able to live with.

CoyDog · June 5, 2001, 05:52 PM

Thanks, guys. I should have said that my interest is hunting only, and I don't want anything too fragile to stand up to field conditions.
Good Shooting, CoyDog

Unkel Gilbey · June 5, 2001, 06:42 PM

CoyDog,

Another important thing to consider is the throat of your rifle. I seem to recall that 270 Winchesters have been throated a bit longer then what you would consider to be standard. Either that, or perhaps it was 7mm Mausers...?

At any rate, your factory rifle just might have a long throat, and it would be difficult for you to seat the bullet out long enough to contact the lands for what the target shooters would deem the perfect seating depth, and still have enough of the bullet in the case neck. This would lead to problems!

But so what! You yourself stated that this would be a hunting rifle, so go with what your loading manual says is the recommended OAL for that bullet. If you have acceptable accuracy from there, Cool! If not, then you can start to monkey around by seating it a .001 in/out until you find the optimum depth.

Or at least, that's what I'd do! Good Luck!

Unkel Gilbey
ps: Are you are Vermonter?

Big Bunny · June 5, 2001, 07:59 PM

I think on a .270 for hunting your can be far too "bench-resty" and while I concur with the remarks made so far...the real test IHMO is accuracy in the field with a rugged bullet that can stand up to a bit of "serious BIFFO".

Rounds have been known to fall apart in magazines and in the pouch, also stuck in the lands due to contact with the rifling.....and 75gn of powder through the action !! [Just great when you are 160Km from home and the game is "ON".]

Try the factory seating and OAL for a start.
If it works...great. If it doesn't... start experimenting alone the lines as the above posts by our TFL respected experts.

Take care and have fun.

BB

CoyDog · June 5, 2001, 08:26 PM

Unkel Gilbey: No, I'm in Wyoming.

I think the throat is long on my rifle; at least too long to seat the bullet out that far. I've never been impressed with factory ammo accuracy in this rifle. The best I've seen has been 1.25" for three shots at 100 yards. I'm hoping that handloading can improve this.
CoyDog

June 5, 2001, 01:37 PM	#1
CoyDog Senior Member Join Date: December 15, 2000 Location: Wyoming Posts: 163	I've been loading for my handguns for the past year, and am now starting on rifle reloading. I'm looking at using 130 grain Nosler Partitions for a .270, using H4831 powder. In determing the best bullet seating depth, I measured the distance to the lands of my rifle. This was very long, compared to .270 factory ammo. If I tried to seat the bullet so it would rest just short of the lands, it would barely be seated in the cartridge neck. The rifle magazine is quite long (Rem 700) and would accomodate such a long cartridge, but I wonder about proper seating. Is there a rule of thumb about how deep in the neck that a bullet must be seated? Thanks, CoyDog __________________ "A man's choice of weapons is a portal into his thoughts, his values, and his character."

June 5, 2001, 02:14 PM	#2
45Colt Member Join Date: December 2, 2000 Posts: 60	Bullet Seating Andy, my best advice would be for you to go to the Benchrest site, Benchrest.com. These folks know nearly everything there is to know about bullet seating, etc. In a nutshell, though, you need to make sure that you seat your bullet at least 1/2 caliber into the case. e.g. if you're shooting a .270, it should be seated at least .135 into the case, or more. (Not too deep, though, check the manuals for OAL). Next step is to make sure that your round will fit into the magazine if you're huunting with it, and that it doesn't get battered by recoil when in the mag, and then shift the OAL. That plays hell with consistency of accuracy. HTH Walt

June 5, 2001, 05:52 PM	#4
CoyDog Senior Member Join Date: December 15, 2000 Location: Wyoming Posts: 163	Thanks, guys. I should have said that my interest is hunting only, and I don't want anything too fragile to stand up to field conditions. Good Shooting, CoyDog __________________ "A man's choice of weapons is a portal into his thoughts, his values, and his character."

June 5, 2001, 08:26 PM	#7
CoyDog Senior Member Join Date: December 15, 2000 Location: Wyoming Posts: 163	Unkel Gilbey: No, I'm in Wyoming. I think the throat is long on my rifle; at least too long to seat the bullet out that far. I've never been impressed with factory ammo accuracy in this rifle. The best I've seen has been 1.25" for three shots at 100 yards. I'm hoping that handloading can improve this. CoyDog __________________ "A man's choice of weapons is a portal into his thoughts, his values, and his character."

June 5, 2001, 04:52 PM	#3
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	Most cartridge designers try for one caliber seating depth. These benchresters, though, routinely seat out to less than that. Be aware that the farther out you seat the bullet, the more fragile the whole bullet-to-cartridge neck interface becomes. Out beyond a half caliber depth, some caliber bullets can be pushed over with finger pressure, depending on neck tension. Benchresters have been known to use very slight neck tension deliberately, so that on chambering a round, the bullet contacts the rifling and easily slides back into the neck on bolt rotation. A round assembled in this manner can come apart if chambered, not fired, then ejected. So remember, the benchresters need to know what you're going to use the rifle for, if you ask them for advice. Without telling them that, they might give a benchrest answer you may not be able to live with.

June 5, 2001, 06:42 PM	#5
Unkel Gilbey Senior Member Join Date: February 26, 1999 Location: Danby, Vermont Posts: 349	CoyDog, Another important thing to consider is the throat of your rifle. I seem to recall that 270 Winchesters have been throated a bit longer then what you would consider to be standard. Either that, or perhaps it was 7mm Mausers...? At any rate, your factory rifle just might have a long throat, and it would be difficult for you to seat the bullet out long enough to contact the lands for what the target shooters would deem the perfect seating depth, and still have enough of the bullet in the case neck. This would lead to problems! But so what! You yourself stated that this would be a hunting rifle, so go with what your loading manual says is the recommended OAL for that bullet. If you have acceptable accuracy from there, Cool! If not, then you can start to monkey around by seating it a .001 in/out until you find the optimum depth. Or at least, that's what I'd do! Good Luck! Unkel Gilbey ps: Are you are Vermonter?

June 5, 2001, 07:59 PM	#6
Big Bunny Senior Member Join Date: August 9, 1999 Location: New South Wales - Australia Posts: 605	I think on a .270 for hunting your can be far too "bench-resty" and while I concur with the remarks made so far...the real test IHMO is accuracy in the field with a rugged bullet that can stand up to a bit of "serious BIFFO". Rounds have been known to fall apart in magazines and in the pouch, also stuck in the lands due to contact with the rifling.....and 75gn of powder through the action !! [Just great when you are 160Km from home and the game is "ON".] Try the factory seating and OAL for a start. If it works...great. If it doesn't... start experimenting alone the lines as the above posts by our TFL respected experts. Take care and have fun. BB