Ladder Results

[whelen35]

I was shooting my XP-100 at 300 yards today and I had some results on my ladder test which did not make sense to me. When I have shot ladders for my rifles the shots tend to rise and go to the right. My XP-100 chambered in 7mm BR went to the right with it's shots but lowered. How would you interpret the results?

120 grain Nosler Ballistic Tip with VV 133 and Federal Match Primer
1)29.9
2)30.2
3)30.5
4)30.8
5)31.1
6)31.4
7)31.7
8)32.0
9)32.3
10)32.6
Also shots 5 -10 were compressed and when seated were 5 thousands longer than 1-4

 

[2506]

Your test with a pistol length barrel came out like it should have. The slower the bullet is moving the more time the barrel has to rise in recoil before the bullet leaves the barrel thus the higher your POI would be on the target. The faster your bullet moves because of more powder the quicker the bullet exits the barrel and the barrel does not have as much time to rise in recoil so your POI would be lower. This is seen more in pistol length barrels than in rifle barrels because the less weight of the pistol lets the barrel recoil up quicker.

 

[SooStan]

2506 hit it right on the money

 

[whelen35]

Thank you guys for all the information. I thought something was horribly wrong with my bedding or the barrel. I am going to try a ladder with Reloader 7 and H322 as well.

 

[whelen35]

Lynn,
Let us know what your friend's XP-100 does with the ladder. My barrel is the original factory barrel, but the stock was changed. I have attached a picture of it.

 

[2506]

Go and read the report on the 6mmBR Striker Pistol on the home page. He got better groups and stopped stringing at long range by using bunjie,sp) cords to tie the pistol down to keep it from recoiling too much.

 

[warthog97]

I don't mean to hijack the thread, but I am hoping someone can step back and explain ladder testing a little. I've been reloading for over a decade, but it's been primarily for hunting/plinking, not precision shooting. One of my favorite sayings that some folks can have 20 years of experience, and other have 1 year of experience 20 times. I'm starting to feel like the latter as I transition into precision reloading...

I like the concept of firing one shot per charge increment checking for velocity and pressure,granted the former is statistically irrelevant and the latter is a guess at best, but at least you get an indication...) and I assume you're looking for a 'node' where a fixed powder change results in nominal vertical dispersion. Since I don't know what I'm looking for in a latter test, but willing to try new things, I would either be tempted by the 5-6 line due to the limited vertical variance. So my question, why is load 8 the load of choice? What did you see that made it the favorite? Thanks!
-bnw