OzFclass

Thanks Norm.I ordered 200 cases on Monday,so I hope I will have them by the weekend.

Given these cases are heavier, I would think it prudent to batch by volume after a second firing to see how consistent they are.

.248WIN wrote:Has anybody measured the water capacity (volume) of these case yet ,I class my class by volume rather than case weight,and would like to know how consistent there volume is .

I have just started loading with my Bertram brass and have done some measurements before and after firing using my dodgy digital scales that I can share. Scales are only accurate to 0.2 the but I thought that is good enough to get an idea and do some comparisons with Lapua cases.

Out of the bag the Bertram brass pieces weighed between 212.4 and 217.6 gn. A similar lot of many times fired neck turned Lapua brass ranged between 196.4 and 198.4 gn.

After firing the Bertram brass once I did some volume comparisons. I don't like wet cases and was going to reload these immediately so I measured the weight of five each pieces of Lapua and Bertram with AR2209 filled to the top and leveled off across the neck with a small screwdriver. All very scientific.

The Lapua brass charges varied between 63.8 and 64.6 gn. The Bertram brass charges varied between 61.2 and 61.8 gn.

I repeat that the scales used are only accurate to 0.2 gn if you're lucky but I consider good enough for these initial comparisons. I have a new set of digital scales in the post and will do a similar test with them after another firing as suggested by Dave.

One thing I can add is that the Bertram brass is very hard on the thumbs if using a Lee hand primer. I will be changing that part of my loading setup.

Steve.

Footsore wrote:After firing the Bertram brass once I did some volume comparisons. I don't like wet cases and was going to reload these immediately so I measured the weight of five each pieces of Lapua and Bertram with AR2209 filled to the top and leveled off across the neck with a small screwdriver. All very scientific.

I have an old can of Winchester ball powder I use for that. I'm hoping that it settles better than stick.

Hi All,
I received 100 cases and found the weight spread similar to Steve's and same with the lapua.
If they weight sorted the brass and charged a bit more (for that service) would be better.

As a follow up to my case comparisons I loaded up three identical loads in each of 50.2gn 2209 with mollied 180gr Bergers in Bertram cases and Lapua cases. At 100 yards both shot one hole groups. The Lapua cases gave velocities of 2754 2740 and 2738. Bertram cases with same load gave 2774 2780 and 2787 fps.
I found this result very interesting.

Steve.

Footsore wrote:As a follow up to my case comparisons I loaded up three identical loads in each of 50.2gn 2209 with mollied 180gr Bergers in Bertram cases and Lapua cases. At 100 yards both shot one hole groups. The Lapua cases gave velocities of 2754 2740 and 2738. Bertram cases with same load gave 2774 2780 and 2787 fps.
I found this result very interesting.

Steve.

Goes to show how great those Bartlein barrels are.

Denis those barrels are great. So is that new Bertram brass. I would like to claim first dibs with a 60.7 using it at 300 yards at Beaudesert last Sunday.


Steve

G'day Bertram brassers, how's the brass going?

What number firings are you guys up to with 180's, Shehane or .284W, MV and powder charge?

How are the primer pockets feeling compared to first 1st, 2nd and 3rd primings?

Moly coated bullets or not?

Cheers,

So far have only loaded cases a maximum of twice. Once with a lightish load to fireforming to chamber and a few of these I have used for load development.
The fireforming loads work out to be quite good. 125.13 at 500 yards yesterday using AR2213sc, some old CCI_200 primers, mollied 168 bergers and some 162 amax for the second relay.
Case capacity is a bit less than Lapua brass so you can expect velocities to be higher for a given charge. So work up loads with this brass DONT go straight to an old favourite.
Load development so far shows me that this brass will give accuracy at least as good as Lapua brass with very respectable ES figures using AR2209 and 180 Berger VLDs.

Interested to hear how others are doing.

Steve.