Pls help - Quickload estimate

I’ve developed a nice and accurate 158 gr cast SWC 38 Spl +P load using BE-86 and need someone’s help to run a Quickload calculation to give me an approximate estimate of this load’s psi:

Load info for Quickload:

38 Spl +P
158 gr Missouri cast SWC (12 bnh)
Load - 4.9 grs BE-86
CCI 550 primer
OAL 1.460” (crimped in bullet crimp groove)
Hi 953
Lo 918
Avg 931
ES 35
SD 9

Appreciate you helping me out and providing this load’s estimated psi. I’m estimating it at approximately 18,100 psi +/- based on its velocity compared to Alliant’s reloading data.

I wish Quickload was compatible with IPads, I would be very interested in purchasing it if it was…

“This is my load for use in my revolver only. Always refer to current published load data, it’s instructions and all applicable information first before reloading. I like to use data from Speer, Lyman and Handloader Magazine.”

I have not purchased the update for my QL and what I have dose not include BE-86.

I looked at the on-line Alliant data, and was quickly disappointed in their info (again). Your load is between what they list for a cast out of 38 SP and a J word out of a 38 SP +P. However, they do not list pressures for their loads.

When using QL, the other inputs that can be helpful would be bullet length and barrel length. However, the QL "barrel length" is breech to muzzle, so it includes the length of the cylinder. However, it does nothing to account for losses due to cylinder gap or loose fit cylinder throats. I find QL predictions to be very poor for revolvers in general. Thing are better when you can "benchmark" a QL prediction against actual load data with pressure in psi. Given the way that Alliant does things now, you would need to find better data from some other source.

Thank you for your informative response.

Regarding pressures, I usually work up slowly, as we know is most prudent, being very aware of how my load’s velocity compares with the muzzle velocity envelope listed in the published load date.

Your approach is very reasonable and I would probably do very similar.

Two points of caution for the OP or anyone else reading this.

Working up loads while watching for "pressure" is reasonable for a bolt action rifle with >55,000 psi, but is much less useful for ammo under say 35,000 psi. Can you tell the difference in appearance between a 18,000 psi load and a 25,000 psi load? I have guns that I load to both pressures and there is not enough difference in the removed ammo to spit at.

The second point is again, using a chrono with revolvers. Using a chrono may be the best tool available, but I have seen many posted cases of two different near identical revolvers shooting a good bit different for velocities. It helps if you have reference info that makes sense (loads assembled exactly as per load data that you then ran over a chrono in your gun).

I like the way the OP is not trying to run his loads at what he thinks would give him max pressure. Generally speaking this is just a hobby and there is no reason to risk injury or gun damage jut for a little more speed.

As an additional note, Load data without pressure info bothers me. I agree that they usually run J Word loads up near max, but this is not true for cast loads.

In 357 Magnum, Alliant has a max load of 8.1 grs behind a 158 gr cast bullet. Velocity from their 6 inch test barrel is 1,156 fps (their max load so I guess that is MAP 35K psi). With the velocity I’m obtaining with 6.5 grs of BE-86 and 158 gr cast from my Ruger 4 5/8, extrapolated through a six inch tube, I’m biting at the heels of Alliant’s velocity. I will not exceed 6.5 grs BE-86 with the 158 gr cast bullet in my 357 Magnum…1,080 fps in 4 5/8 inch with 158 gr cast SWC is good enough for me (a 38-44 in 357 Mag cases).