Is it just pressure that operates action

[mattd]

Trying to find something that will work the action on my mini 14. 55g FMJ loads operate it with 24-26 of varget. Been loading Unique under my 53g bator bullet. Great accuracy at 8.5g, but up to 9.2g hasn't operated the action. According to my manual 9g unique is over 40k on the pressure, but 25g of varget is less then 35k. What am I missing?

[country gent]

Pressure curves are way diffrent between those 2 powders. Pressure and volumn of gas at the gas port is important to functioning as well. Unique may be peaking and then dropping enough at the port that it dosnt have the pressure. Is the action opening part way or not at all? Have someone watch the action or put a piece of light tape between bolt and front reciver ring to see if action is starting to open.

[madsenshooter]

Doesn't have the pressure, or the volume. 9gr of powder can only make so much gas. I know it sounds odd for .223, but a caseful of H414, or W760 will likely keep you within cast bullet pressures, and produce enough volume to work it. Having said that, don't start with a caseful, start around 23gr and work up your load.

[mattd]

That's along the lines of what I was thinking. It starts to open. A friend said that at 8g it was opening about 1/4 of the way. By myself shooting higher loads. Don't have those powders, and can't ever find powder. Could try the varget or 4064.

[country gent]

What velocity are you wanting to achieve? with cast loads those 2 powders may be more velocity than the boolets will take resulting in leading issues. Powders are becoming available slowly, Keep an eye out and or check online. I had several friends that would "swap" small amounts of powder for testing purposes. In 223 1/4lb of powder will give a very good idea if it worth working with.

[mattd]

Whatever works! Couldn't be happier with 8-8.5g of unique. Except for manually working the bolt. Will keep that one in my back pocket

[madsenshooter]

Reason I posted above is that I've had some success in a 1/8 twist 6x45 using slow powders, bullets were hard as linotype though and velocities were 2100fps-2300fps. Accuracy-wise 4198 won with a 2000fps load, shot single shot.

[JeffinNZ]

Combination of the two. You need enough pressure to cycle the operating system but in enough volume at gas port. If you peak out prior to the gas port she ain't gunna cycle.