Newbie here with an introduction and a question.

[TRyan]

Hello everyone! I'm new to long range shooting and reloading, but I've been shooting and hunting since I was 10. I've hunted with several different rifles and calibers that ranged from Ruger M77 .243 & .300 WinMag, & .300 Weatherby Mag. I sold them all and went with a custom rifle build. I found this site and I think I've found the right place for some good info.

Here's my rifle: 7mm/08
Rem 700 S/A trued
McMillan A3 Sporter
Lilja #4, 22", fluted barrel, chamber cut to fit Berger 168gr. VLD match hunting bullets
Jewel trigger set at 2#
PT&G fluted bolt and handle
Nightforce NXS 2.5x10x42
Nightforce rail and rings

This is a hunting rifle. I've been working up a load using Norma brass, 168gr VLD, RL 15 powder. So far I've found that the best groups are with a .005 jump using a max recommended charge of 38.6gr. I haven't tried jamming them yet because I'm afraid of hunting with rounds that might get stuck when unloading live rounds. The advice in Berger's reloading manual says stay back .010 or more from the lands if hunting.

Here's my questions: Any hunters out there jam their Berger hunting rounds or load them just touching the lands? Is it best to either have a jump or a jam, but try and stay away from just touching the lands due to pressure spikes when seating right at the lands? I don't have a chrony yet.

I haven't went went any deeper with bullet seating depth than .010 jump. With the chamber/ throat cut for the only bullet I plan on shooting, is it logical to think that I really don't need to try a .050 or greater jump and that it will shoot better closer to the lands? I shot 2 five shot groups that were .75 moa at 100 yards seated at .005 jump. .010 wasn't as good.

Thank you, here's some rifle porn for you;gun)

 

[Predator 22]

10 thousands off is the minimum I will use for hunting loads. I'm still fairly new to bergers but I usually start 10-20 thousands off and then keep jumping them 15-20 thousands at a time then fine tune 3-5 thousands at a time on each side of the best group.
Here is a link to what berger recommends. VLD: Making it Shoot | Berger Bullets

 

[TRyan]

Thank you for the reply. I'm going to play around with the seating depth around .010 off the lands +/- a couple thousands.

 

[PGJPJ]

Very sweet package! Excellent set-up.

I can't help yet though. I just got my loads ready for seating depth testing. I have a Pac Nor barrel in 280 Ackley, and I had them cut the chamber for 168 grn Berger VLD Hunting as well.

My test loads are 0.015", 0.050", and 0.090" off the lands, I just need to make it to the range.

 

[el matador]

You probably won't notice much difference between .005" and .010". Try the method described in the link posted by Predator 22 and you should be able to find a good seating depth for your rifle. It's nice to have a chamber set up so that you CAN touch the lands and still fit rounds in your magazine. Doesn't mean you have to load them that long but at least you have the option if that's where you find accuracy.

I would back off the powder charge a couple of grains for the seating depth test. You never know how your rifle will react to changes in seating depth. Once you have your COAL figured out you can go back and try different powder charges with your method of choice.

 

[Barrelnut]

Good advice above about dropping the charge and doing a little more testing.

I shoot the 140 VLDs in a Creedmoor. They shoot excellent when just touching the lands, BUT they also shoot excellent, if not better at .040 off! You maybe able to find a sweet spot further away from the lands, if so that is better when hunting. You also might be able to use bigger powder charges further from the lands for more speed.

 

[TRyan]

Thanks for the help and comments. I took your advice about dropping off the powder a couple grains and spread the seating depth test out to bigger jumps. I loaded for .010 jump, .025 jump, and .040 jump, 2 groups of 3 shots for each depth. I did shoot two more 3 shot groups of .010 jump with the hotter load I had made up as well, after finding that my rifle seemed to like that jump the best.

None shot terrible as all groups were better than 1 moa. But the clear winner is the seating depth around .010 off the lands, with group sizes at .321 moa, .556, .749, and .956 moa. I did get a pretty sweet group at .025 jump too, at .5 moa.

Still need to get a chrono and figure out max pressure and velocities.

Is it safe to assume most people end up loading their rounds right at or above maximum recommended powder levels, keeping safety in mind of course?

Thanks,

Tim

 

[el matador]

Is it safe to assume most people end up loading their rounds right at or above maximum recommended powder levels, keeping safety in mind of course?

I would guess most people are finding their accuracy loads somewhere between 95% to 102% of the published max loads. That's a wide enough range to find a good accuracy node in most cases, provided you have a powder and bullet that your gun likes. Do not load max charges or above max charges without starting lower and working up! There are a ton of ways to work up a load but for me it goes like this:

Using a starting load I test seating depth (like you've done)

Then I test powder charges in roughly 1% increments from 95 to 102% of published max load. I like to load 3 rounds each at 95, 96, 97, 98, 99, and 100%. Then I load 1 round each at 101 and 102% for pressure testing, just in case I shoot all my groups and still have not seen pressure signs. Depending on what I see after shooting my groups I may repeat the test, focusing more on a specific range of powder charges. For example, if my best group comes at 97% I might do another test at 96, 96.5, 97, 97.5, 98.

If I don't get any good groups during the first round of testing I will usually try a different powder or bullet and repeat the test.

From these tests I hope to find out 1) What my accuracy load is, and 2) What my max pressure load is. I like to have my accuracy load at least 1% below max with 2-3% being ideal. That way I know I won't have issues when the temperature changes.

Once I have a load figured out I'll shoot some 5 or 10 shot groups over the chronograph just to verify that everything is good. If not I might tweak it a little.