Loading into the Lands.

[CMBTshooter]

How catastrophic would loading a 220 PT into the lands over a starting load of IMR 7828 in a .300 Win Mag? When you load into the lands how hard would closing the bolt be? I ask because I'm starting with the 220 PTs and with a max COAL of 3.480 it chambers effortlessly. I have no accurate way of measuring the distance to the lands.

 

[AzDak42]

Have you tried using the once fired case trick to get a ballpark idea of how far off you are?

I've never found a rifle that had a problem or didn't shoot reasonably well at max COAL.

 

[Guy Miner]

Make up a dummy cartridge, with a slit cut into the neck of your case. Use a hacksaw or a small cutting wheel while the case is supported in a vise.

Then you have a slip-fit for the 220 gr Partition (or any other bullet) and you can find how far out the bullet can be seated. Just seat it long, and gently close the bolt. When the bullet engages the rifling, it will be pushed deeper into the case.

Gently eject it and you've got your overall length, to the rifling.

Note - it's possible to get some errors, but do it a few times and measure each time. You'll get 'er figured out.

*I think this beats jamming a bullet into the lands with a case full of 7828 behind it! :mrgreen:

Guy

 

[AzDak42]

Make up a dummy cartridge, with a slit cut into the neck of your case. Use a hacksaw or a small cutting wheel while the case is supported in a vise.

Then you have a slip-fit for the 220 gr Partition (or any other bullet) and you can find how far out the bullet can be seated. Just seat it long, and gently close the bolt. When the bullet engages the rifling, it will be pushed deeper into the case.

Gently eject it and you've got your overall length, to the rifling.

Note - it's possible to get some errors, but do it a few times and measure each time. You'll get 'er figured out.

*I think this beats jamming a bullet into the lands with a case full of 7828 behind it! :mrgreen:

Guy

I can't remember which one of the guides had this, but it's a modified version that doesn't require cutting a case. Follow the same process, but instead of cutting a slit in the neck, just use a once fired case and use a screwdriver to create just a small indent on one side of the neck. It will give enough tension to hold the bullet in place.

 

[CMBTshooter]

Have you tried using the once fired case trick to get a ballpark idea of how far off you are?

I've never found a rifle that had a problem or didn't shoot reasonably well at max COAL.

I tried this but I'm really not sure if I'm doing it right.

 

[AzDak42]

I tried this but I'm really not sure if I'm doing it right.

If you do it 3 or 4 times and get a consistent reading, as well as seeing slight marks on the bullet, you're doing it right.

 

[Guest]

Best way I've found is as follows:

1. Size the neck of a fired case. Size it only part way down the neck. I use about .15" as a guide, but in some cases I have to go farther down to get a reliable hold.

2. Seat a bullet very shallowly in this case, just maybe .1" of bullet heel in the case, just enough to be straight and not flop around. Oh, and no powder or primer in this case, either. Please, please, please make sure you remember that little gem.

3. Color over the bullet with a sharpie, or smoke it with a candle.

4. Gently insert the round into your chamber (again, no primer, no powder in this one...) and slide it into the chamber with your thumb, gently.

5. Ever so gently close the bolt. Seriously, I mean close it like it's an egg. Slow and steady wins the race here. You don't want to cram the bullet into the rifling.

6. Optional step - insert a clean cleaning rod into the muzzle, with no tip on it. Gently run that down til it stops against the bullet tip. Don't let it "whack" the tip. Use some sort of brass muzzle guard or a cotton ball around the rod to protect the crown while you're doing this. Lift up the muzzle guard and mark the rod with a sharpie (right at the end of the muzzle). Remove the rod (carefully!!!).

7. Gently open the bolt and slide it back. Don't let the round eject to the floor - catch it with your hand or keep a finger on it so it'll stay in the receiver in front of the bolt. Gently remove the round from the action.

8. If the bullet is still in the case, you're in luck. If not, Use a rod to tap it out of the rifling. Reinsert the bullet just up to the "scratch marks" in the sharpie/smoke indicating the depth to which it was seated.

9. Measure this round with a comparator or just to the tip, but a comparator is better. Write down that measurement.

10. Optional step - Close the bolt, and reinsert your cleaning rod/muzzle guard/cotton ball apparatus. Run it down to the face of the bolt, and again lift the guard out of the way and mark with a sharpie, exactly as you did before (same angle, same process/technique). Measure the distance from the left side of each mark on the rod, and write down the measurement. It should be nearly dead equal to the "head to tip" measurement of your dummy round.

Repeat this process about 3-5x, and look for consistent results. If you're getting within .005 or so, I'd call that consistent. Use the average. If you get a variation of .010 or more, might want to work on technique. Repeatability is the key to this.

Hope that's helpful.

 

[HTDUCK]

I take a case and partially neck size it.
The coat the base of the intended bullet and inside of the case neck with RCBS case lube, just a thin layer.
Insert case into chamber and try to close the bolt. If it doesn't close seat bullet .005 deeper and repeat.
Eventually you will get the bolt to close. Measure the OAL .

 

[CMBTshooter]

Ok, I tried the small dent in the neck trick (That will come out when I size right?) and it didn't really work with one dent. After five attempts with measurements ranging from 3.544 to 3.599, I put another small dent in the neck and measured four attempts at 3.513, four at 3.514, one at 3.515, and the last at 3.519.

Am I good to go? These are some loooooooooooooong bullets! Next up are the Berger 185 Grain Juggernaut OTM.

 

[Oldtrader3]

Sounds good to me!

 

[SJB358]

I use the Hornady comparator deal for finding seating depth, but when I don't have a case for a cartridge I'm using, i use a fired case from the rifle, a squeeze the neck slightly with vise grips or pliers. I actually want some decent tension on the bullet. I also color then entire base of the bullet with a black sharpy, then insert and extract it, measuring between, 3-5 times. I will also use a little of the motor mica or graphite on the bullet ogive area to resist it getting stuck into the rifling. With enough try's it seems to be plenty accurate and I don't have to waste an expensive case.

CMBTshooter, sounds like you got it nailed and certainly close enough to begin load work.

 

[CMBTshooter]

Scotty I'm going to have to try the graphite on the ogive. The 185 Bergers kept getting stuck in the rifling so I gave up for the time being.

 

[SJB358]

Even a little Imperial Sizing Wax may help too