Newby questions
Preface by saying I pulled some info from JD338 and DrMike in getting a starting point for 2 loads.
1. 250 AB/Retumbo
2. 225 TTSX/Retumbo (Pulled this from #3 manual also)
Nosler Brass, 215GM
Both were loaded to 3.72 oal. Lands are +\- 3.8 for both 250 ab and 225 TTSX.. (Wyatts box installed in XCRII, along with bedding in a B&C Alaskan stock)
I loaded the 250 AB's 97,97.5, 98, 98.5, 99. Loads above 97.5 increased in significance of compression. I did find this surprising based on previous posts here that identified 98.5gr load in "normal" mag length.
The 97.5 and 98.5 loads both showed promise with 3/4" groups @ 100. (These were within the first 20 rands out of the gun). The 98.5 load had SD of 3, ES of 6 (granted only 3 rounds, but great start) but had slight ejector marks, so I elected to load up another batch of 97.5 to dial in the load/confirm previous results.
At this point I was happy to be close to a load to use on a mid October elk hunt.
The next trip to the range did not go as well, basically two shots into 1/2, then the 3rd about 1" away.
I finished this trip by shooting the 225 TTSX rounds I had loaded. 92,92.5,93,93.5 gr. These all grouped similarly until the 93.5, which also shot at about 3/4". (Also with low 4 SD/ 7ES)
Not wanting to give up on the 250's I loaded up another 12 and gave it another try the following weekend. It was a hot day (low 90's). Groups where in the 1" to 1.5" range, and continued to have 2 close and 1 off. Chrono results showed wide swings in velocity, which seemed to correlate to the group sizes. 17 total of the 97.5 load avg 2952, SD 58, ES 156!. (2880, 3036)
Feeling like I was running out of time, I went back to the 225 TTSX/93.5 load. SD's opened up 13, ES 40. Averaging 2980 @ 15 ft. Groups shrunk back down when I did my part. Last 2 groups attached. The small one is 3 shots also.
So, to the questions:
Any ideas for the 250 load?
Did others experience significant compression at 98.5? (at shorter oal)
Is the 98.5 showing slight ejector marks hot? The marks would indicate yes, but that doesn't jive with the increased capacity from 3.72 oal when comparing loads from board members.
Is the capacity of the Nosler brass less than Fed/rem?
It seems like groups got better approaching the pressure limit, is this typical?
How much more "room" for velocity do I have for the 225gr?
That's probably enough rambling from me for now. Thanks in advance.
Preface by saying I pulled some info from JD338 and DrMike in getting a starting point for 2 loads.
1. 250 AB/Retumbo
2. 225 TTSX/Retumbo (Pulled this from #3 manual also)
Nosler Brass, 215GM
Both were loaded to 3.72 oal. Lands are +\- 3.8 for both 250 ab and 225 TTSX.. (Wyatts box installed in XCRII, along with bedding in a B&C Alaskan stock)
I loaded the 250 AB's 97,97.5, 98, 98.5, 99. Loads above 97.5 increased in significance of compression. I did find this surprising based on previous posts here that identified 98.5gr load in "normal" mag length.
The 97.5 and 98.5 loads both showed promise with 3/4" groups @ 100. (These were within the first 20 rands out of the gun). The 98.5 load had SD of 3, ES of 6 (granted only 3 rounds, but great start) but had slight ejector marks, so I elected to load up another batch of 97.5 to dial in the load/confirm previous results.
At this point I was happy to be close to a load to use on a mid October elk hunt.
The next trip to the range did not go as well, basically two shots into 1/2, then the 3rd about 1" away.
I finished this trip by shooting the 225 TTSX rounds I had loaded. 92,92.5,93,93.5 gr. These all grouped similarly until the 93.5, which also shot at about 3/4". (Also with low 4 SD/ 7ES)
Not wanting to give up on the 250's I loaded up another 12 and gave it another try the following weekend. It was a hot day (low 90's). Groups where in the 1" to 1.5" range, and continued to have 2 close and 1 off. Chrono results showed wide swings in velocity, which seemed to correlate to the group sizes. 17 total of the 97.5 load avg 2952, SD 58, ES 156!. (2880, 3036)
Feeling like I was running out of time, I went back to the 225 TTSX/93.5 load. SD's opened up 13, ES 40. Averaging 2980 @ 15 ft. Groups shrunk back down when I did my part. Last 2 groups attached. The small one is 3 shots also.
So, to the questions:
Any ideas for the 250 load?
Did others experience significant compression at 98.5? (at shorter oal)
Is the 98.5 showing slight ejector marks hot? The marks would indicate yes, but that doesn't jive with the increased capacity from 3.72 oal when comparing loads from board members.
Is the capacity of the Nosler brass less than Fed/rem?
It seems like groups got better approaching the pressure limit, is this typical?
How much more "room" for velocity do I have for the 225gr?
That's probably enough rambling from me for now. Thanks in advance.
