Nosler 300 gr 45-70

[JEBar]

question for those who have experience with Combined Technology Ballistic Silvertip Bullet .... CT Ballistic Silvertip® bullets combine all the features of Nosler Ballistic Tip® hunting or varmint bullets, but with the addition of an advanced Lubalox® external treatment developed by Winchester that reduces fouling and creates less barrel wear to promote longer barrel life. .... does the Lubalox® coating perform as advertised .. .. video demonstrating the Combined Technology bullet ===> https://www.youtube.com/watch?v=u7IV1JVxpx8

[bdbrown66]

OK, so I finally got some decent weather to shoot my ladder test. Loads were as follows:

Brass - Starline
Powder - IMR 4198
Primer - CCI 200
Bullet - Nosler 300gr BT
4 rounds each with 48.0gr, 49.0gr, 50.0gr, 51.0gr, and 52.0gr
Distance - 100 yards

I shot each group over the chrono, placed about 15' from the muzzle. Here is the chrono data for each load:

48.0 49.0 50.0 51.0 52.0
Avg. velocity 1761 1868 1882 2001 2041
Extreme spread 123 34 116 78 56
Standard deviation 50 14 49 32 27

Now for pics of each group. The first two groups (48.0 and 49.0) had one shot each that went above the target. These rounds were shooting several inches higher than what I had my scope set for. I eventually dialed the scope down just to keep it on the paper.

48.0:

49.0:

50.0:

51.0:

52.0:

As you can see from the chrono data and the pics, I hit a sweet spot at 49.0, and then the group really opened up at 50.0, before starting to tighten up again as the charge increased. According to the Hodgdon load data, I should be safe to take this load on up to about 57.2gr. I probably won't go quite that high, but I am going to see if the group continues to tighten up above 52.0. I'll work up another ladder from 52.0 - 56.0 and see how that goes. Stay tuned...

[JEBar]

very interesting indeed .... really looking forward to the "rest of the story" .... please monitor the primers as you go up the ladder .... you may want to keep tabs on if / at what load they start backing out,

[bdbrown66]

very interesting indeed .... really looking forward to the "rest of the story" .... please monitor the primers as you go up the ladder .... you may want to keep tabs on if / at what load they start backing out,

Will do, of course, but I'm not expecting that. Reason being, the load data goes up even further for the Ruger #1, etc. I would think that if loads at that higher level were blowing primers, Hodgdon wouldn't publish them. But yes...I will keep an eye on things.

[JEBar]

Will do, of course, but I'm not expecting that. Reason being, the load data goes up even further for the Ruger #1, etc. I would think that if loads at that higher level were blowing primers, Hodgdon wouldn't publish them. But yes...I will keep an eye on things.

with the same casings designed to be used in the Ruger #1, nor would I .... I'm not used to seeing 3 very different loading levels like it is for 45-70 .... are the chamber sizes for all three the same, I simply don't know .... like you, as you have proven by the meticulous way you are approaching developing the load for your rifle, I tend to take baby steps .... using a Chrony helps but, other than keeping an eye on the primers, I have no way to measure chamber pressure .... in every manual you see, they have strong warnings to not exceed maximum load recommendations .... that's fine when they at least come close to agreeing .... when they don't, for me, it can be confusing

[bdbrown66]

I just took a close look at the primers as I was putting the brass in the tumbler for cleaning. There was virtually no noticeable difference between the primers from the 48.0 loads and the 52.0 loads. Maybe just a very slight bit of cratering at 52.0, but very minimal. None of the primers were flattened or backed out.

[bdbrown66]

JEBar, something you may find of interest. After cleaning up the brass that I shot on Saturday, I set about loading up my next ladder test, this time from 52.0 - 56.0gr of IMR 4198. To avoid any length issues, I trim my brass to 2.095", which is the recommended trim length for 45-70 (SAAMI max length is 2.105"). I am crimping right on the cannelure on the Nosler BT's. When I got up to 56.0gr of powder, I could not quite seat the bullet to the same depth as I had been previously. The difference was not great, but it was noticeable. However, by shaking the powder in the casing a bit before seating the bullet, it allowed it to settle enough that it would seat to the same depth as before. Based on that, I would say that 56.0 is pretty much a max load for the Nosler BT. If you trimmed the case at the SAAMI max of 2.105" you could get a little more, but not much. Assuming, of course, that you're going to crimp on the cannelure.

I'll let you know how things go when I shoot this batch.

Cheers,
Brian

[JEBar]

great info .... looking forward to your reports

[bradf]

I usually find a second node with just about everything I load. For my H010, H4198 with Sierra 300 gr HP has a nice node at 55 gr. But the BEST node was at 58.5 gr which was 120 fps faster and a SD of 6.9 vs 28 for 55 gr. There was no sign of excessive pressure. I trim to 2.095 as well.

[bdbrown66]

Ok, another round of testing this evening. Loads were from 52.0 - 56.0 of IMR 4198. I'm not going to post pics of all of them, but I did find a very nice load at 54.0. Average velocity 2125 fps, with extreme spread of 27 and SD of 14. I am quite happy with this load and will load some of them up to test out to 200 yards or so. The group I shot today was 1.5" with one flyer. Apparently I pulled the one shot just a little, because the other three measured .367". I can live with that. Oh...this was at 100 yards.

One important note: I examined all casings, looking for signs of pressure. I could not see any difference whatsoever between the primers on the 52.0 loads and the ones at 56.0. No flattening, cratering, backing out, etc. Nothing at all that would give me pause.

Keep shooting,
Brian