Reliable squib loads; How low can you go?

[Slowbalt]

Been having some successes (and many failures, but lets focus on what's important ), with severely reduced loads. The three most promising ones are running between 550 and 700 FPS in a 308. My question is how low can I go before I get unreliable results (stick one in the bore)? I am mainly concerned with temperature fluctuations (northeast, 90 in the summer, down to 25 below in the winter).

[Outpost75]

Great question!

Jacketed bullets have more bore drag and often present a poor fit in the bore which enables gas leakage around the bullet. Therefore the velocity needs to be high enough to ensure reliable bore exit. In cartridges similar to the .30-30, .308 or .30-'06 it generally takes a minimum velocity of about 750 fps to ensure 100% reliability of bore exit under all conditions, 5-6 grains of Bullseye. If the bore is clean and lightly oiled, firing a light bullet for the caliber, such as 110-grain .30 Carbine pulls, you may be able to get a dozen rounds off with 4.5 grains of Bullseye before sticking one, but 6 grains is 100% reliable.

Best for low-velocity "cat sneeze" loads are soft, lubricated lead bullets which fit the bore well and are light in weight for the caliber. Using sized lead buckshot or 98-grain lead .32 pistol bullets you can go down as low as 500 fps in a clean barrel, using 3 to 3.5 grains of Bullseye, for very low noise and good accuracy to 25 yards

Heavier cast bullets with a longer bearing surface, like #311299 require a heavier load, 4.5 to 5 grains of Bullseye as a minimum, but 6 grains is more reliable, accurate and still subsonic for use with a "can" with good accuracy to 100 yards.

[Slowbalt]

Currently running LEE C312-185-1R (sized to .308, already had on hand both the mold and the sizer, so decided to try it before buying more gear) pure-ish (plumbing) lead lubed with LEE alox, in 308 cases with the flash hole enlarged to 9/64, FED large rifle magnum primers and dealer's choice of 2.5gr 700x, 2.5gr Tightgroup or 4.0gr Trailboss. Getting 1-1.5 in at 50 yards. In my testing no bullets ever stuck, with minimum velocities of 500 or so FPS.

Was hoping to stay in the 2.5gr range... Will have to test and see I guess...

[Walks]

Wasn't the Lyman #308413 originally designed as a squib bullet ?

[Texas by God]

Gas check or not on the Lee bullet?
Spot on advice about going light for squibs; lubed .310" rb will work just fine-and easy to push out if too sqibby.

Sent from my SM-A716U using Tapatalk

[Slowbalt]

No gas check as of now. Not there yet in my testing

Hope they don't turn out to be useful, I'd rather use them in more spicy loads.

[uscra112]

What Outpost75 said. I've done several, but I didn't find them very useful, given that there's always low-power .22 ammo available. But it was fun watching the bullet sail slowly downrange thru the scope.

I discovered in the course of these experiments that a squib load so low that the bullet doesn't exit is an easy way to slug a barrel.

[Thumbcocker]

Paco Kelly wrote about very soft heavy boolits with light charges of powder in various rifles. He called them silent loads or something similar. I'm sure a Google search will turn up his articles.

[James Wisner]

A couple of years ago I started using Unq and the Lyman # 311440, which is a 150 gr cast bullet.

I wanted to find the a nice mouse fart load for the 308 Win, in a Remington 788

I started with 7 grs and worked up to 11 grs.
As I started shooting at a 100 yd target, I would get the click of the firing pin and the smack of the flat nose bullet hitting the backstop.
Working up to 9 grs I would get the click of the firing pin and about half of the time a boom of the bullet breaking the sound barrier and a bigger smack of the backstop.
At the 10 gr part of the trial all of that load would boom, so it was no longer sub sonic

Hope this helps.
JW

[Char-Gar]

Wasn't the Lyman #308413 originally designed as a squib bullet ?

Nope...Squib was the name of the guy who designed the bullet.

[Char-Gar]

It may just be a matter of terms, but I thought a "squib" load was one that malfunctioned and probably did not exit the barrel. I am certain I will be corrected if If got that wrong. Reduced velocity loads are called "gallery loads".

[SSGOldfart]

Char-Gar Sir your spot on we always tried to avoid a "squib" which is a bad thing I'm sure they are talking about "gallery" loads.

[17nut]

I have gotten as low as @180fps from 0.8grains Tinstar in a 45LC with a 255grain Lee bullet. From a 7½ Colt SAA. You could see the slug fly.

With well lubed bullets i see no reason you cant go below 400fps, just use dacron to hold the powder against the primer or ignition will be erratic at best.

[17nut]

I have gotten as low as @180fps from 0.8grains Tinstar in a 45LC with a 255grain Lee bullet. From a 7½ Colt SAA. You could see the slug fly.

With well lubed bullets i see no reason you cant go below 400fps, just use dacron to hold the powder against the primer or ignition will be erratic at best.

[15meter]

https://castpics.net/subsite2/ByCali...er%20Loads.pdf

This is probably a good place to start with low velocity loads, then work your way down from there.

I've done several of them, the 45-70 was probably the most fun, @ 200 yards, point of aim was ~30 degrees above horizontal to hit a dinger 3 feet off the ground.

Eventually. It took a while for the slug to get there, and it still rang the dinger with authority.

[Cap'n Morgan]

I once managed to get a cast 150 grains .264 boolit to stick in the barrel. The cartridge was based on an expanded Hornet case.
I can't remember the amount of powder, but I was working my way down from a small amount of Bulls Eye to begin with.
The gun was a singleshot break-open shotgun with an insert barrel. When I opened it, there were still pressure enough to blow the case out of the chamber.

The plan was to have a subsonic load with more punch than the ordinary .22, but I never got around to finish the gun. Oh, well...

[ulav8r]

I started reloading in 1968 using a 308 W Lee Loader and Lee dippers. Using bullets pulled from military 30/06 and Unique I tried some light loads. Started at around 6 grains and worked my way down. With a dab of dacron filler and just under 3 grains of powder, the bullet traveled about 10-12 feet. Did not try that light of a load again.

[uscra112]

Good point about using a fiber filler. These tiny loads are extremely position-sensitive.

But use kapok or toilet tissue. Dacron melts into a nasty mess at these low temperatures. Ask me how I know.

[ulav8r]

Right after that one shot, I started using malt o meal as a filler. It left the bore shiny but not sure I would trust it if left in storage for a long time. Not used it enough to be sure one way or the other.

[35remington]

I advise against using cereal or grex type buffered loads when high amounts of filler and very small charges of smokeless powder are used. Often the filler does not clear the case or barrel and bad juju may subsequently result with a succeeding shot.