Lightweight Build

[300RUM]

Another lightweight stock option is High Tech Specialties. I got one for $200 delivered for a lightweight 7mm-08AI build. I had to do the final fitting in the receiver area and barrel channel, bed it, cut it to length and install the recoil pad. Loaded and ready to hunt the rifle weighs 7.2 lbs. It is possible the stock may not handle a magnum cartridge. You would have to ask them about that. 717 - 484 - 0405

[Cell4soul]

Another lightweight stock option is High Tech Specialties. I got one for $200 delivered for a lightweight 7mm-08AI build. I had to do the final fitting in the receiver area and barrel channel, bed it, cut it to length and install the recoil pad. Loaded and ready to hunt the rifle weighs 7.2 lbs. It is possible the stock may not handle a magnum cartridge. You would have to ask them about that. 717 - 484 - 0405

Thanks for the info, I will check them out.

[Cell4soul]

I went to Sportsmans Warehouse today to pick up some .224 bullets to reload for my dad's .225 Winchester. They just so happened to have all of the reloading supplies I plan to use for this build. I picked up 8lbs of Hodgdon H4831SC, 3 boxes of 162 ELDX and 2 boxes of Norma 7 mm SAUM brass.

[Cell4soul]

Just picked up what I will probably use as my lightweight scope for this build. Cabelas had the Leopold VX6 2-12x42 on sale for $500 off retail. It wasn't my first choice for this build, but should be a good lightweight scope for a pack rifle. I couldn't pass up on th deal.

[Cell4soul]

Ordered my Precision Armament recoil lug. Also ordered a set of Talley Lightweight scope rings. I pretty much have everything, now just waiting on the reamer.

 

For barrel break in, I am going to follow the Proof Research recommended break in procedure. Is there any benefit to working up loads with different charge weights during the barrel break in? Or, should I just load some ammo at SAAMI specs for overall length and stick with a fixed powder charge with a charge weight on the lower end of the pressure scale?

 

I appreciate any advice.

[cjl2010]

Both my rifles we did load developement during barrel break in. Both shot .5 groups. are you using factory firing pin and spring?

[Cell4soul]

Yeah, factory firing pin and spring. Good to hear you did load development during break in. Should save some time and money. I am guessing I will have to verify after break in and initial testing.

[cjl2010]

Yes definitely verify. I think my stw barrel has sped up a little since I've got about 150 down the tube.

[lancetkenyon]

My break in is as follows:

Shoot one

Shoot one

Shoot one

Repeat....

 

I always load about 10-15 for sight-in at a mid charge weight according to book. Shoot to zero rifle @ 100 (+1.3" approx.), 200 (true zero), 400 (verify drop estimation).

 

Then immediately start my 400 yard ladder testing procedures.

[Cell4soul]

My break in is as follows:

Shoot one

Shoot one

Shoot one

Repeat....

I always load about 10-15 for sight-in at a mid charge weight according to book. Shoot to zero rifle @ 100 (+1.3" approx.), 200 (true zero), 400 (verify drop estimation).

Then immediately start my 400 yard ladder testing procedures.

So no cleaning of the copper fouling between initial shots? I appreciate the advice.

[Zeke-BE]

My break in is as follows:

Shoot one

Shoot one

Shoot one

Repeat....

 

I always load about 10-15 for sight-in at a mid charge weight according to book. Shoot to zero rifle @ 100 (+1.3" approx.), 200 (true zero), 400 (verify drop estimation).

 

Then immediately start my 400 yard ladder testing procedures.

 

 

Can you give a little more insight with a ladder test and why at 400 yards. I guess i interpret it differently, so explain like your explaining it to a beginner please

[Cell4soul]

 

My break in is as follows:

Shoot one

Shoot one

Shoot one

Repeat....

I always load about 10-15 for sight-in at a mid charge weight according to book. Shoot to zero rifle @ 100 (+1.3" approx.), 200 (true zero), 400 (verify drop estimation).

Then immediately start my 400 yard ladder testing procedures.

 

 

Can you give a little more insight with a ladder test and why at 400 yards. I guess i interpret it differently, so explain like your explaining it to a beginner please

I think he has a few previous posts showing his ladder tests, but I always like his input. His attention to detail is second to none.

[lancetkenyon]

A very quick description of my 400 yard ladder test procedures.

 

1. Sight rifle in, and verify drop at 400 yards.

2. Load 1 round of each charge weight, from starting weight, to a full 2 grains above book max. Bullets should be loaded.jammed into the lands if possible. This will give you the highest pressure, and will show where your rifle's max load is.

 

For example, if book minimum is 39.0gr of H4350, and max is 44.5gr. of H4350, load in .5 grain increments from 39.0 to 46.5gr.

39.0, 39.5, 40.0, 40.5, etc.

 

Then go set up a target at 400 yards. Verify POI on a separate target that you are pretty much center hits. The target will need to be between 16-24" tall.

 

Start with your lowest charge weight, and shoot. Mark the shot as #1.

Continue to shoot and mark each shot, always using the same point of aim. Do not adjust once you start. Stop shooting at the first sign of pressure. Flattened or cratered primer, stiff bolt lift, ejector marks or swipes on case head, etc.

 

You should see 2-4 consecutive rounds in a good horizontal plane with little vertical dispersion , within 1" or so. Meaning charge weights have the same POI. Like 42.0, 4w.5, 43.0, 43.5 all within an inch vertically. These are called an accuracy node. Where variation in charge weight and velocity do not make difference in vertical.dispersion. where the barrel pauses for a microsecond in the sine wave during the barrel flex when the bullet leaves the barrel.

 

 

You can see two distinct nodes on this target.

Shots 1-3 are a low node, and shots 6-8 are a higher node. Even 5 is close to the same vertical elevation at 400 yards. This gives you wiggle room in charge weight and velocity differences that will not effect POI very much downrange, and allows the best chance for accuracy. You can see 4, 9, 10, are scattered up and down.

 

Here is another rifle load workup I did, but at 300 yards. I prefer 400, but this was all I could do that particular weekend. You can still see two nodes. 1-3 & 6-9.

 

 

Here is my .300RUM ladder test at 400. You can see a great node 9-11 at the top.

 

 

This is a .300WM I did development for. Two nodes again. 3-5 & 7-9.

 

 

Here is my 7RM ladder test. Again, two good nodes. 5-8 & 11-13.

 

[Cell4soul]

Awesome stuff.....as always, thank you for imparting your knowledge.

[WampusCat]

Those ladders are great at highlighting nodes and the winners get even more clear the farther out the test can be shot.

 

Something else worth mentioning on a new build. I like to revisit load development after the first 1-200 rounds through a new barrel. They will normally "shoot in" and pick up some more fps than during initial load development. This can result in a slight change of chamber pressure and has the potential to change barrel harmonics. Sometimes there isn't enough change to worry about as far as group size and sometimes a tiny tweak to the recipe will really tighten things up again. Just food for thought if you are trying to squeeze the most out of your rifles capability when you get to that point.