[Mannlicher]

I was at the range early this morning. I used the Chrony Beta to check some of my hand loads. 170 grain Speer FP, over 34.5 grains of IMR 4320 in once fired Remington cases. Winchester primers.

My 16 inch barrel Marlin 336Y gave me an average of 2135, with a high of 2150 fps. Accuracy was within an inch at 100 yards,

The Marlin 336 straight stock saddle ring rifle, 20 inch barrel, turned in an average of 2206, with a high of 2242. Again, outstanding accuracy.

This is not all that much different from what Remington factory 170 gives me, but it sure less inexpensive to shoot.

 

[Redbear]

Good work! I have use of one. They aren't a necessity but sure can be helpful and fun.

 

[Halwg]

I was at the range early this morning. I used the Chrony Beta to check some of my hand loads. 170 grain Speer FP, over 34.5 grains of IMR 4320 in once fired Remington cases. Winchester primers.

My 16 inch barrel Marlin 336Y gave me an average of 2135, with a high of 2150 fps. Accuracy was within an inch at 100 yards,

The Marlin 336 straight stock saddle ring rifle, 20 inch barrel, turned in an average of 2206, with a high of 2242. Again, outstanding accuracy.

This is not all that much different from what Remington factory 170 gives me, but it sure less inexpensive to shoot.

Interesting on a couple counts. Firstly I don't see many folks using IMR-4320 in the 30-30, but I would think it would do a good job. Secondly, your load is 2 grains over the max listed on the Hodgdon web site. I assume you aren't getting any pressure signs.

 

[Mannlicher]

Some years back, I was playing with 4320. I had been given 600 once fired Remington Brass, and had a lot of the 170 Speer FP sitting around.
The starting load I began with was 30 grains. I was using what was, at the time, the 'current' Speer Manual, their #8. I gradually moved up to the max load of 34 grains. While velocity was ok, accuracy was not.
I went down to 33.5, and got no relief. I went up to 34.5, and voila, the sweet spot.

It has been my 'go to' load ever since. That it is a tad over is not a concern to me, as I have some 40 years experience with this load now.

No, I am not getting any signs at all, of excessive pressure. As always, the caveat is "do not use my load on my say so".

 

[Halwg]

If truth be known, all of my 35 Remington loads exceed the max listed in the loading manuals. Just don't try this at home, folks! ;D