230 gr Boolite in a 7.5 inch barrel.

[Tayous1]

So loaded up some the other day and took it from 8.2gr of Lil gun up to 9.5 gr but could not get the weapon to cycle the next round came close with the 9.5 gr but kind of worried to take any higher than that.

Any advice other than using the 230gr in my 16" barrel or enjoying having a single shot 7.5-inch barrel? Thanks for the advice and help!

[dellet]

I would start by using a bullet.

All kidding aside it might not hurt to try a jacketed bullet to test function first.

Check the diameter of your bullet, if it’s undersized you will have a gas leak. Should be .309” for cast

What was the velocity, and why didn’t you stop at 9.5 grains?
Were you seeing pressure signs?

Buffer weight and carrier type might make a difference.

[Tayous1]

Stopped at 9.5gr only because load date I found said max 8.2 gr I was reading at another online form a guy said he was able to get 9.2 gr and that cycled his 8.5 inch barrel.

[Tayous1]

Also never had an overpressure issue so don't know what it looks like. Tried to look it up but the photos did not help just trying to be safe.

[dellet]

Most subsonic data is deceptive. It lists a max load to remain below 1050 fps. For an example here is data that is pressure related, not velocity and includes both sub and super.



All data is listed for a 16” barrel, so needing more powder to get the same velocity is normal. The rifle should have full function tho with very close to the same charge. This is why it’s important to know actual velocity.

There are a lot of things can can cause your problem, but knowing all the details is the only way to figure it out. I hit the basics in the earlier post, but suppressed or not will make a huge difference. Port size, load details all come into play.

I have a 230 grain bullet and 9.5 grains of Lil’gun and the gun won’t cycle is a question that is to vague to give any more than help other than something is wrong with your rifle.

[Tayous1]

Thanks so where are you measuring to get the .309? I did my cast load and a few other factory .308 at the wideist point best I got was 300 that's was with my cast a factory.

[dellet]

If the largest diameter you got was 300", either your measuring device or the bullets need to go in the garbage can.

First make sure that the caliper or MIc is zeroed correctly, and also measure the inside of the neck of your brass if possible. If the bullets are only 300", they will probably just drop in.

Here is a pretty typical bullet drawing and dimensions. Basically the parallel portion of the bullet, the bearing surface, will be .308" on a jacketed bullet and .309" on cast or powder coated.If it had a boat tail it would taper off the back end.



This is typical of a cast bullet that is designed for powder coating, or what a jacketed would look like, only the bearing surface would measure .308" instead of .310"



If your bullet is undersized, getting it to cycle will be very difficult

[Tayous1]

Zeroed the calipers and tried it again I must have had something off as they are all factory and cast are reading .309 to .310. Loaded 10 of them up with the 9.5 gr H110 shot them in my 16" barrel and the 7.5-inch barrel. Had more trouble with the 16" barrel it would not even extract the brass after the shot. The 7.5 inches had no problem extracting the brass it again would not load the next round.

The brass looked fine I might try that 10.2 gr H110 and see how it works it seems it just needs a little more. Dellet thanks for the help!

I don't know how many more times I'm going to cast for this as my MP- mold .311 410 HP comes in tomorrow. Still have to say the 230gr is fun to shoot out of the 7.5 inches and even when I missed the steel target at 100 yards I could still hear the thud when the bullet hit the tire backstop.

[Tayous1]

So was reloading today and thought why not load two of the 230 gr with 10.5 gr of H110 just for S&G. Loaded them in a magazine with my 130 gr following them.

This time I had no problem with them cycling and loading the next round. Also I could not tell the difference in the primers from the 130 gr and 230 gr. Thanks for the help!