Litz BCs 300g OTM

[youngbuck]

I've been using the shooter app for over a year now. I've had pretty good results with it, especially with the Litz tested G7s in both of my other 2 LR rifles. It appears Shooter hides the Litz tested values. Today I shot my 338LM for the first time, shooting 300gr Berger OTM. I shot at 1k twice today. I shot that far to check my scope to make sure it was plumb. Both shots were a couple feet low. I suppose my scope's clicks could not be exactly 1/4 moa, but they would be off 10% if that was the case. The scope is an IOR 6-24x56. I just went over my input values and everything seems to match up. Anybody using a G7 thats not Litz? I input the listed the G7 and it seems to be higher than tested by Bryan. Anybosy else running into this?

 

[Broz]

Re: Litz BCs 330g OTM

I was having trouble a while ago with this in my 338 lm when I used the Lintz file from the bullet library. Then while discussing it with BignGreen he suggested maybe that file was old and was using the first predicted BC's for the Berger 300's. Now I use a G7 of .419 for the first step and I am good to 1200 or so then I add another stepped BC.

Jeff

 

[youngbuck]

Re: Litz BCs 330g OTM

Thanks Broz, I was hopin you would chime in. You have a lot of time with these bullets. I tried .419, and it is actually higher than Bryan's tested BC. The correction is about 1 MOA less in elevation than the Litz tested (at 1K). I only have 2 LR shots, so I may need more time and testing. If neither number doen't work out, I'll end up testing a lot, and fundging the BC down a little bit. I was working on a ragged hole @ 100 untill I pulled a flier. It was still about a 1MOA group with no load development and cleaning the barrel after every shot.

 

[Broz]

Re: Litz BCs 330g OTM

Sounds good, I am sure you will get her figured out. What is your powder charge and barrel length? Also what are you using for velocity?

Jeff

 

[youngbuck]

Re: Litz BCs 330g OTM

I'm running 2735 avg, 25 ES with 89gr H-1000 on a 26" barrel. I think I have a lot of room to gain some velocity. If I can crack 2800, I'll be happy. I don't think I'll have any problems getting there.

 

[Broz]

Re: Litz BCs 330g OTM

I'm running 2735 avg, 25 ES with 89gr H-1000 on a 26" barrel. I think I have a lot of room to gain some velocity. If I can crack 2800, I'll be happy. I don't think I'll have any problems getting there.

Id say you are good there as far as I can tell.

Jeff

 

[BryanLitz]

Re: Litz BCs 330g OTM

I'm not saying the BC stored in the Shooter library can't be wrong, but it's still a very good idea to shoot the 'tall target test' at 100 yards to verify the scope clicks are true. 10% isn't out of the question for scope adjustment error.

Good shooting, sounds like you're off to a great start.

Take care,
-Bryan

 

[youngbuck]

Re: Litz BCs 330g OTM

Thanks for the help Bryan. I need to shoot the "tall target test" anyways, to check my scope for plumb, after I moved it. I never thought of doing it that way. I've never had a scope that wasn't exactly 1/4MOA, so I've never had to deal with that. I dont think it will be a big deal if thats the case once I get the correction factor. Lets say my clicks are 10% short, would my correction factor in shooter be .9? How ever it works out, it gives me an excuse to burn up some more powder

 

[Rocky Mountain]

Re: Litz BCs 330g OTM

I'm not saying the BC stored in the Shooter library can't be wrong, but it's still a very good idea to shoot the 'tall target test' at 100 yards to verify the scope clicks are true. 10% isn't out of the question for scope adjustment error.

Good shooting, sounds like you're off to a great start.

Take care,
-Bryan

Scope click error input is over looked alot. The shooting scope test I have found is to easily miss read because of human error I like to clamp the rifle and wind it around an inch target grid at 100 yards

 

[youngbuck]

Think I may have found the problem. I'm using a Forster micrometer seating die. On my second batch of loads it seems the stem is too shallow. It is slightly deforming the tip. It was definitely worse on my second batch. I sent an email to Forester to see if they sell a VLD style stem/plug. If they don't, I'll drill it out. I'm sure this second batch of loads wont shoot real well at distance, but I'll get to find out where I see pressure signs. I loaded 3 each in .5gr increments from 89-91gr of H1000. Once I get the seater stem worked out, I'll shoot the close target test and measure POI change vs MOA adjustments made.

 

[Broz]

Think I may have found the problem. I'm using a Forster micrometer seating die. On my second batch of loads it seems the stem is too shallow. It is slightly deforming the tip. It was definitely worse on my second batch. I sent an email to Forester to see if they sell a VLD style stem/plug. If they don't, I'll drill it out. I'm sure this second batch of loads wont shoot real well at distance, but I'll get to find out where I see pressure signs. I loaded 3 each in .5gr increments from 89-91gr of H1000. Once I get the seater stem worked out, I'll shoot the close target test and measure POI change vs MOA adjustments made.

Youngbuck, Most of the time that pressure will show up just after 91 gr in a 338 lm. I have made it to 92.5 . But lots are different so the 1/2 gr stepps are best. Also it sounds like you might be running pretty high neck tension. Do you have a way to back it down? Bushing change?

Jeff

 

[youngbuck]

I would have to agree about the neck tension. My old man actually loaded this last batch. All my reloading stuff is at his house. He knows what he is doing and even asked me last night how the seating went for me during the first batch. He said the neck tension seemed higher than the first run. I'm using a forster FL sizing die. It looks like they only offer oversized expander balls up to .308. I suppose I'll have to bite the bullet and buy some bushing dies. That whole process of bushing dies is new to me, one of the reasons I went with the Forster FL die. Thanks for the info, I have some reading to do. I've only used plain RCBS FL dies for my rifle stuff.