DIY drop tube?

Suther

Suther

CGN Ultra frequent flyer
Rating - 100%
27   0   0
Location
Fraser Valley
Looking for suggestions for a DIY drop tube. I was loading some D4350 this past week and even at the start load listed by Nosler I am getting a bit of compression, which obviously only gets worse as I go. Im loading for a 7mm-08, using nosler 1f brass and a Hornady 139gr GMX. I figured I'd use their data for IMR4350 and the E-tip bullet and work up a load.

https://load-data.nosler.com/load-data/7mm-08-remington/

Start is 42gr, max is 46gr. The 46gr they list as 100% load density, but not compressed. However I was getting a bit of compression at 42gr and by 46gr there was significant compression, enough that I had to adjust my seating die to keep them fitting in my magazine. My Speer manual lists up to 48gr for a 145gr bullet in the 7mm-08. I checked to see how full that would make my cases, and its almost completely full - close to the top of the neck.

This powder turned out to be too slow for my purposes (46gr only gave me 2446fps from a 20" barrel) and I picked up some RL17 to try next, but I feel like I'm going to run into heavy compression with this powder too (max load from the Barnes data for the 140TTSX is 47.8g and compressed).

So, with all that in mind, can anyone suggest an affordable home-made drop tube that might allow me to get a the powder in the case without compressing it so much?
 
Last edited:
Aluminum arrow shaft. Or my favorite is copper tube just a little smaller than the case mouth so you can flair it slightly and get a good deal.

Take a caliper and walk around the Home Depot and you will find something.
 
vagrantviking said:
Aluminum arrow shaft. Or my favorite is copper tube just a little smaller than the case mouth so you can flair it slightly and get a good deal.

Take a caliper and walk around the Home Depot and you will find something.
Click to expand...

That's a good idea too! Might have to take a ride down to Rona after work.
 
I literally just put my finger over the case mouth and tap it on the bench to settle the powder. Seems like it works just fine.

Alternatively, copper line and a flare tool would work ok to make a universal drop tube.
 
I made mine out of brake line tubing. End is already flared for cartridge, cut to desirable length and thread your funnel for the brake line fitting. I believe it is 1/4 inch.
 
vagrantviking said:
Aluminum arrow shaft. Or my favorite is copper tube just a little smaller than the case mouth so you can flair it slightly and get a good deal.

Take a caliper and walk around the Home Depot and you will find something.
Click to expand...


Do you reckon a carbon fiber shaft would cause static sticking?
 
My setup is a half-inch wood dowel drilled right into my bench. To that I screwed in 2 eyelet screws to hold the tube. The tube is brass (quarter inch I think or close to that) bought from a local hobby/craft store. The contraption is topped off with an aluminum Saturn funnel.
 
RePete said:
You can fire up the tumbler and touch the post with the ase.
Click to expand...

Tumbler!? I dont need no stinkin' tumbler! (by which I mean I dont have one. lol)

Once I get a piece of tube, I will try both a drop tube and the vibrating toothbrush, and see how the two methods stack up to each other. Thanks for all the ideas everyone!
 
Suther said:
Tumbler!? I dont need no stinkin' tumbler! (by which I mean I dont have one. lol)

Once I get a piece of tube, I will try both a drop tube and the vibrating toothbrush, and see how the two methods stack up to each other. Thanks for all the ideas everyone!
Click to expand...

Then you can brush your teeth at the same time.
 
I have a wire brush wheel on my bench grinder. That thing is so out of balance if I turn it on even though it is 10' away it vibrates the bench like crazy. haha
 
You must log in or register to reply here.
Back
Top Bottom