I thought I would add another post regarding load development for my .338 Lapua. As some of you may be aware, I have tried various powders in my .338 LM. The list of powders are - RL25, RL22, H4831SC, Retumbo and now H1000. I'll list my rifle specs again:
M2008 Action
28" Bartlein Barrel, 1:9.7 twist, MTU Contour
Badger FTE Break
All put into an AI chassis
Here is the link when I first got the rifle and initial load development - http://www.snipershide.com/forum/ubbthre...rue#Post1281494
Here is the link to my other load development: http://www.snipershide.com/forum/ubbthre...rue#Post1556572
Approximately 1 week ago, I decided to try Retumbo with 300gr SMK's. I wanted to do this because I like Hodgdon powder and to see if I could bring down my ES. My ES with RL25 was hovering around the 20fps range.
<span style="font-weight: bold">NOTE: I am using 300SMK's which have been coated with BN.</span>
I ran an OCW at 100 yards and here is what I found when using Retumbo:
I could push the 300SMK to 2850fps but the average ES for the 5 different loads I tried was still around 20fps. Also, I found that I could not get any decent groups using Retumbo. My best group (3 shots) was around .75 MOA.
<span style="text-decoration: underline">H1000 Development:</span>
Yesterday I decided to try H1000. I did this after talking with Tom Sarver at the TVP shoot on 1-3-2010. So I did another OCW test at 100 yards using my standard brass prep and using charge weights from 90.5gr to 93.0gr's. I used the 90.5gr charge as my sighters and therefore I shot those all in a row. After that, I proceeded with the OCW as usual. The target is below:
I was very pleased as I saw a reduction in my ES along with the groups tightening up. The largest group was .844" and the smallest at .192". Obviously the 91.5gr was my first node (.192") with 93gr being the second node (.294"). The 93gr load is tempting, but the ES was 21 while the 91.5gr load had an ES of 8. I will now try this at distance and see if everything continues to hold up.
A few observations during my load development with the powders listed above (this applies to my rifle so please keep this in mind. YMMV):
- RL25 and RL22 do perform well, but I found them to be more temp sensitive than Hogdgon (no surprise here)
- I also found RL25 and RL22 to be inconsistent in terms of grouping at distance
- H4831SC and H1000 are definitely "cleaner" burning
- It seems as though a really slow burning powder (i.e. RL25, Retumbo) may not be optimal for my .338 Lapua. A slightly faster powder gave me better results.
- The 250gr Scenar's are fairly predictable in terms of flight even at a mile (Shot these at TVP in January)
In closing, I hope this has helped people when loading for the .338 Lapua Magnum. Obviously rifles vary and what works well in mine, may not work well in yours. <span style="text-decoration: underline">Also - All information given in these posts are "at your own risk". You are responsible for you own reloads and developing those reloads for your rifle. </span>
Thanks again to Tom Sarver, George and Moon, Marty, Zac Smith, Desert HK, Lt. ArcLight and many other people who were gracious enough to share information.
Tony
M2008 Action
28" Bartlein Barrel, 1:9.7 twist, MTU Contour
Badger FTE Break
All put into an AI chassis
Here is the link when I first got the rifle and initial load development - http://www.snipershide.com/forum/ubbthre...rue#Post1281494
Here is the link to my other load development: http://www.snipershide.com/forum/ubbthre...rue#Post1556572
Approximately 1 week ago, I decided to try Retumbo with 300gr SMK's. I wanted to do this because I like Hodgdon powder and to see if I could bring down my ES. My ES with RL25 was hovering around the 20fps range.
<span style="font-weight: bold">NOTE: I am using 300SMK's which have been coated with BN.</span>
I ran an OCW at 100 yards and here is what I found when using Retumbo:
I could push the 300SMK to 2850fps but the average ES for the 5 different loads I tried was still around 20fps. Also, I found that I could not get any decent groups using Retumbo. My best group (3 shots) was around .75 MOA.
<span style="text-decoration: underline">H1000 Development:</span>
Yesterday I decided to try H1000. I did this after talking with Tom Sarver at the TVP shoot on 1-3-2010. So I did another OCW test at 100 yards using my standard brass prep and using charge weights from 90.5gr to 93.0gr's. I used the 90.5gr charge as my sighters and therefore I shot those all in a row. After that, I proceeded with the OCW as usual. The target is below:
I was very pleased as I saw a reduction in my ES along with the groups tightening up. The largest group was .844" and the smallest at .192". Obviously the 91.5gr was my first node (.192") with 93gr being the second node (.294"). The 93gr load is tempting, but the ES was 21 while the 91.5gr load had an ES of 8. I will now try this at distance and see if everything continues to hold up.
A few observations during my load development with the powders listed above (this applies to my rifle so please keep this in mind. YMMV):
- RL25 and RL22 do perform well, but I found them to be more temp sensitive than Hogdgon (no surprise here)
- I also found RL25 and RL22 to be inconsistent in terms of grouping at distance
- H4831SC and H1000 are definitely "cleaner" burning
- It seems as though a really slow burning powder (i.e. RL25, Retumbo) may not be optimal for my .338 Lapua. A slightly faster powder gave me better results.
- The 250gr Scenar's are fairly predictable in terms of flight even at a mile (Shot these at TVP in January)
In closing, I hope this has helped people when loading for the .338 Lapua Magnum. Obviously rifles vary and what works well in mine, may not work well in yours. <span style="text-decoration: underline">Also - All information given in these posts are "at your own risk". You are responsible for you own reloads and developing those reloads for your rifle. </span>
Thanks again to Tom Sarver, George and Moon, Marty, Zac Smith, Desert HK, Lt. ArcLight and many other people who were gracious enough to share information.
Tony
