First liability statement if you try this at home
1. I don’t recommend this.
2 . Take all normal safety precautions safety glasses etc.
3. Use someone else’s gun

Have you wondered.....If the statement that Hornady One has no effect on powder or primers was true.
Draw your own conclusions but it seems to me to be true. Sunday afternoon I needed to load 300 WM for my brother’s Elk rifle. I have the gun for a while as he won’t be needing it anytime soon so I decided to play with some powders I have not tried in this caliber. I had some Reloder 25 that I don’t even remember where it came from but it’s old enough to have a price of 22.00 on it.
So I took 15 pieces of sized Nosler brass and marked 5 as control and loaded as I normally would.

Then the next five I sprayed a liberal amount of One Shot directly into the case.....enough that I poured some out as I turned it over. Let them sit about 20 minutes and dumped the same charge of R25 and loaded.

Next five I did the same spray into case BUT then after the Chargemaster threw the charge I dumped the powder in another extra pan an soaked it with One Shot then poured into case. It didn’t really want to go as it clumps badly but I forced it in let them sit a few minutes and seated bullets.

Today I fired 3 of each at the range checking speeds on the Labradar. I save two of each to see what happens after a few months of sitting. I won’t have this rifle so It may be a while until I can test.

Pictures show results

Control group


One Shot sprayed in case only



One Shot case and n powder

Hornady should now market one shot as a solution to lower ES and SD! Ha ha

What the...

Here is the target. This rifle has a skinny foreend so my front Rest lets it wobble side to side so the strung out group one shot was me for sure but other two looked good when the rifle went off
Control is in middle left group is just sprayed in the case only and the right group is One Shot spray d on powder as well as in the case.

I like that you tested this on your brothers gun

Very interesting!

Very interesting. I would have thought obvious changes, especially the group with the powder sprayed.

Great report -

I understand one shot to be a liquid, only test if I’d add is to fill up 5 cases and let them sit overnight (no powder) to see what effect the liquid has on the primer.

Not that anybody would purposely reload like this BUT for rather “for science” purposes does one shot saturating a primer for 24+ hours have a negative effect on ignition.....

I get what your saying but in away it did sit with the primer soaked as any residue drained to bottom and then I seated bullets and they sat in the reloading block for over 24 hours before I took them to the range.

That’s interesting, I figured ANY liquid would neutralize primers.

Thanks for sharing

Ok follow up to this post for the sake of unscientific data. I saved couplr rounds of the load that I sprayed the case nearly full of One Shot then dumped it out and poured the powder in. Fired it last week and it shot the same velocity as before no issues at all.
This next one to me is pretty impressive.....I also kept a round that I not only sprayed the inside of the case but I also sprayed the powder soaking it with One Shot then loaded it. So it’s been marinating for almost 6 months... fired perfectly and shot in the group at the same velocity as before. So there you go FWIW seems there is no harm in spraying One Shot inside your case.

Thank you for sharing the results of this 5 month experiment.

I have never seen any ill effects from using one shot, but bever took testing that far

Not to be negative, but I don’t think the sample size is large enough to be statistically significant. If the temperature is 70 degrees on Monday, 71 on Tuesday, 72 on Wednesday, it doesn’t mean that it will be 430 degrees a year from now. Small sample sizes can produce very atypical results.

so yes and no. The smaller sample size can be less reliable but unless you know the overall variation it can be applicable (albeit in a limited case). Your temperature comment has to do with conditions of testing and extrapolating beyond the limits of the study. For example i can test barrel length from 16-24 in and show velocity increase. But at a certain point the increase stops, which is beyond the limits of the study (IE i can get 5000fps with a creed barrel that is long enough)

It would not be fair to say that one shot has no impact based on this test. But it would be fair to say that given this rifle, and this powder, and this load that there is no negative impact to being coated with one shot. If more of us were to try it with varying loads, varying powder it would become more statistically significant

I find the test interesting. If i was reloading anytime i soon, i would consider trying it.

That’s pretty neat

Can't even remember where i got it come but I ways sprayed my cases with One Shot and then rolled them on this pad thing (RCBS i think). I literally heard a few weeks ago that you can simply spray One Shot all over the all the cases, just let it dry like 20-30 and every case is ready for FL resizing. The video I watch has the person standing about 50 cases on a box and just sprays indiscriminately. I was shocked. I thought you had to use the pad like I;ve been doing.

So basically, is it ok to just spray a bunch of cases and then FL size after they dry?

It works very well for sizing normal loads and I use it for most of my reloading, for a couple I will not use it, making wildcats and one that the chamber is a bit large so it takes a lot of pressure to force those cases into the die. But if doing what most often is needed size the neck and bump shoulder then I have never had an issue using it.

I put the cases in a reloading block and spray them from a downward angle of about 45 degrees from 3 sides

Thx for the info. This will make it a bit faster for me.

retirement is great