The real problem with seriously compressed loads is, that the COL changes a lot.

That little 130 gr Barnes TTSX is a cool bullet.

That second .5 grain below max had the most consistent velocity.  At distance that counts.  
Try Varget powder.

I use the Barnes VOR-TX in my 7mm-08 in 120 grain. It's impressed me so far. I've always been a die hard ballistic tip man for whitetail but I see the appeal for Barnes.

Being a 270 user, and being from Argentina, I always complained, cursed that you only had .30 caliber rifles, I thought the 130 TSX were expensive for no reason, an unnecessary expense, but after seeing them in gel, not only did they show better performance than the 125 Nosler Bottail and the Pro Hunter, so I'll see if I can find them, but otherwise, I'll try making them on my lathe. If anyone has a mold of the dimensions and the hole, send it to me so I can replicate them.

If you’ve ever read Lee’s book,  compressed loads actually become less pressure and not dangerous. Read it

Word of warning, always be aware that compressed loads can stretch over time. Always check the COAL before shooting.

W748. Got it.  Pardon me.

I've been wanting to see videos like this!

We loaded ours with TAC powder at 0.7grs below the Mac and it was still compressed.  We got 3216 out of a Springfield m1a...
3150 out of my 18" ar10

Alaska ballistics was sending this stuff like 3650 in a .300 win 😆

That’s a really good start   Happy hunting

Thanks for sharing

Images of Yosemite Sam come  to mind. 💥🤣🤣

Back in the 80's I used to have an HK 91 in 308 and for the life of me I couldn't get it to shoot better than 2 1/2 to 3 " groups at 100 yds.... I tried  147 , 150 , 155 ,  165 ,168 and 180 gr projectiles , different powders , cases and primers with no luck till I read an article about using 130 grain projectiles.... my groups dropped to 1 3/4 "..... much better , the best load was Federal cases and primers with 4064 powder and Speer 130 HP projectiles..... I tried a compressed load of 50 gr of H380 and groups shrunk again to consistant 1" .... then I tried the same load but with a Federal 215 magnum primer and got 3/4 " groups and at that point I stopped...that compressed load of a true ball powder like H 380 just seemed to need a bit more heat from the magnum primer . It was not a max load and had no signs of pressure . I dont know if todays H 380 is the same but it was quite safe back then.

Here in SA I shoot a worn P14 with oversize Impala bullets (.313”) in PMP cases with S341, a fine ball powder. Long 28” barrel. MV is 2710 fps, quite in line with the ballistics of .303 150gr at 2650fps. Loads are compressed at 44gr, although not in the neck. But I push it down until no more movement is possible. My grandson is absolutely in love with that old rifle.

Great video

WW2 era Mauser barrels are all (except rare mountain troops rifles) 23,6 inches.

Great loads and accuracy.

I did the exact same thing