1st Time Reloading Bergers Question

[Red Ryder]

Howdy,

My question is, do these COAL (nose to base) and cartridge lengths measured with a comparator seem correct. I'm reloading for a 260 and I'm going to use 130 Berger VLDs. I've never reloaded Bergers before and I know they need to be either jammed or backed off ever so slightly - .010 - .020.

To establish preliminary length, I cut slits in the neck of a Rem 260 case to allow for lessened tension and then deburred the slits. Put a tiny bit of light oil on the bullet down to the ogive to try to prevent bullet stick in the rifling.

Here are the measurements I've gotten.

1st - 2.936 nose to base, 2.237 measured with comparator
2nd - 2.808 nose to base, 2.121 measured with comparator
3rd - 2.948 nose to base, 2.250 measured with comparator
4tg - 2.944 nose to base, 2.244 measured with comparator
5th - 2.953 nose to base, 2.253 measured with comparator

I know that these measurements reflect, literally, a jammed bullet and I intend to back them off. I just wanted to know initially, whether these numbers look acceptable. Oddly, these cartridges will feed from an AI mag.

Many thanks for your wise and experienced comments.

 

[One_Man]

Re: 1st Time Reloading Bergers Question

Heres what I do:

Take 3 fired cases and just barely start to size the neck (maybe a quarter of the way).

Now seat three bullets long (dont add powder)

Take the 3 rounds chamber and extract them.

Measure the base to ogive. The three measurements should be very close (within 0.010" of each other)

Average those numbers, then you have the base to ogive number for seating at the lands. If you want to jump subtract from that number and if you want to jam add to that number.

 

[vman]

Re: 1st Time Reloading Bergers Question

Your second measurement looks off compared to the rest.

Give it another few trys but be extra careful and take your time.

The bergers can be a little funny in their response... it was once thought that touching the lands was needed, or close to but it had since been discovered that SOME rifles respond well with a little jump. Every rifle is different and its up to you to do the research to see what works for you.

 

[John L]

Re: 1st Time Reloading Bergers Question

Remember that the measurement you take now with a clean chamber may not be good when your barrel is dirty. I always do my seating depth measurements when the gun is dirty.

 

[bohem]

Re: 1st Time Reloading Bergers Question

Other than your second measurement they seem very close to mine after about 400 rounds through the tube.

I did the following seating depth at a min-charge weight to establish my seating depth.

100yd
0.010" jam
touching
0.010" jump
0.025" jump
0.050" jump

3 rounds each, shoot each group into a seaparate target and compre the group. You'll get a runaway winner usually. Then fine tune the load if you feel the need.

I didn't have to fine tune on the 6.5-06 last time, touching the lands shot overlapping holes and the others would group about 1 MOA for 3 and 5 rounds. The 260 required a touch more work, but not mcuh.