6mm Remington Bullet Seating

burninghXcsoul · June 13, 2013, 11:13 AM

I have been wanting/reading up on reloading for the past couple of months now and after buying a Rockchucker kit 2 months ago and finally being able to get ahold of some 6mm dies, bullets, primers and powder I'm ready to start reloading. So far I have lubed, sized, deprimed and trimmed 40 pieces of brass for my 6mm.

The questions that I have mainly are for seating the bullet. I have 1lb ea of IMR 4064 and IMR 3031. The bullets I bought to load are Hornady Vmax 58 gr boat tails, Nosler Ballistic Tip 55gr Spitzer Boat Tails, and Sierra Varminter 80gr Spitzer Boat Tails.

When I look up the load data supplied by IMR on their website they have data listed for the 55gr NOS BT with a COL of 2.800 for IMR3031. Too easy. They also have data listed for the 58gr Vmax's with both powders for a COL of 2.775. Ok got it.

Now for the 80 gr bullets that I have they are not the exact kind specified in the load data but for 2 different kinds of 80gr bullets they have COL's listed as 2.810 and 2.775. So what one do you go with?

I understand that adjusting the bullet seating depth will adjust the pressure and I really don't want to blow up my Remington 788 by screwing something up. Or would a change within that variance not really make a difference?

I've also read a lot on trying to seat the bullet so its just off of the lands but I don't think I'm there yet in my reloading experience which is absolutely zero at this point.

Jim Watson · June 13, 2013, 11:23 AM

Standard loads in a standard chamber, .035" difference in OAL is not going to affect chamber pressure. Bottleneck cases are less sensitive to that. The original Vihtavouri book had some interesting data, the chamber pressure vs OAL does not vary in a simple way.

If those are your extremes, I would load to the longer one, assuming it fits the magazine and chamber with your bullets different from the reference.

jepp2 · June 15, 2013, 06:43 PM

Quote:

I've also read a lot on trying to seat the bullet so its just off of the lands but I don't think I'm there yet in my reloading experience which is absolutely zero at this point.

Pressure changes should be minor UNLESS your bullet is in contact with the lands. That can increase pressure 5-7K PSI.

Knowing what the maximum OAL for any given bullet is very useful to know. There are many ways to determine this. There are tools that can assist you in determining this. You can cut 4 slits in the neck, seat the bullet very long and the chambering action will shove the bullet back into the case. Many years ago, folks darkened the bullet with soot from a candle or magic marker, and kept loading the OAL longer until your could just see the bullet touched the lands when chambered.

If you don't know what the maximum OAL length is for a given bullet, you are really just guessing at what OAL to use. And you sure don't know for the OAL you choose to use, how far from the lands your bullets are. Just something to keep in mind.

arch308 · June 15, 2013, 07:14 PM

I've got a 788 in 6mm. You can't get close to the lands and still fit in the mag. I wouldn't worry too much about COL. My rifle shoots sub MOA with just about any quality ammo I put in it. It ain't a bit choosy.
You are gonna love that rifle.

June 13, 2013, 11:13 AM	#1
burninghXcsoul Member Join Date: June 13, 2013 Location: South Central, PA Posts: 37	6mm Remington Bullet Seating I have been wanting/reading up on reloading for the past couple of months now and after buying a Rockchucker kit 2 months ago and finally being able to get ahold of some 6mm dies, bullets, primers and powder I'm ready to start reloading. So far I have lubed, sized, deprimed and trimmed 40 pieces of brass for my 6mm. The questions that I have mainly are for seating the bullet. I have 1lb ea of IMR 4064 and IMR 3031. The bullets I bought to load are Hornady Vmax 58 gr boat tails, Nosler Ballistic Tip 55gr Spitzer Boat Tails, and Sierra Varminter 80gr Spitzer Boat Tails. When I look up the load data supplied by IMR on their website they have data listed for the 55gr NOS BT with a COL of 2.800 for IMR3031. Too easy. They also have data listed for the 58gr Vmax's with both powders for a COL of 2.775. Ok got it. Now for the 80 gr bullets that I have they are not the exact kind specified in the load data but for 2 different kinds of 80gr bullets they have COL's listed as 2.810 and 2.775. So what one do you go with? I understand that adjusting the bullet seating depth will adjust the pressure and I really don't want to blow up my Remington 788 by screwing something up. Or would a change within that variance not really make a difference? I've also read a lot on trying to seat the bullet so its just off of the lands but I don't think I'm there yet in my reloading experience which is absolutely zero at this point.

June 13, 2013, 11:23 AM	#2
Jim Watson Senior Member Join Date: October 25, 2001 Location: Alabama Posts: 19,190	Standard loads in a standard chamber, .035" difference in OAL is not going to affect chamber pressure. Bottleneck cases are less sensitive to that. The original Vihtavouri book had some interesting data, the chamber pressure vs OAL does not vary in a simple way. If those are your extremes, I would load to the longer one, assuming it fits the magazine and chamber with your bullets different from the reference.

June 15, 2013, 07:14 PM	#4
arch308 Senior Member Join Date: November 6, 2011 Location: DFW, Texas Posts: 876	I've got a 788 in 6mm. You can't get close to the lands and still fit in the mag. I wouldn't worry too much about COL. My rifle shoots sub MOA with just about any quality ammo I put in it. It ain't a bit choosy. You are gonna love that rifle.