Nic salt shot in DIY | Maths, mixing and storage

A 10 ml bottle does not look like much, yet it sets the strength of the whole mix. In DIY it is not topped into a shortfill that is already made up. It shares the bottle with the base and the concentrate, and every millilitre it takes is a millilitre the others lose. Building a nic salt shot into a recipe therefore calls for the maths before anything is opened, a thorough mix and strict storage once the session is over.

Nic salt shot maths, how much room it takes in the recipe

The amount of nic salt shot a recipe needs follows one formula, the same as for a freebase shot. Multiply the target strength by the final volume, then divide by the strength of the shot. Subtract the result from the final volume along with the concentrate, and the base fills whatever is left.

The formula also works in reverse as a check. Final strength equals shot strength multiplied by the volume of shot poured, divided by the final volume. If the two calculations disagree, the mistake is in the recipe, not in the bottle.

Two recipes, worked out and checked

UK nic salt shots come in 10 ml bottles and are capped at 20 mg/ml by the Tobacco and Related Products Regulations 2016, with 18 mg/ml versions widely sold as well. Their base varies too, 50/50 at Make My Vape or 70VG/30PG at DarkStar, so read the ratio as carefully as the strength. Both examples below use one full 50/50 shot and a 50/50 base, and show the result for each strength.

Recipe 1, 20 ml for a pod

One 10 ml shot in 20 ml gives 20 × 10 ÷ 20 = 10 mg/ml with a 20 mg/ml shot, or 18 × 10 ÷ 20 = 9 mg/ml with an 18 mg/ml shot. With 10 % concentrate (2 ml), the base is limited to 20 − 10 − 2 = 8 ml.

By weight, at roughly 1.15 g/ml for a 50/50 base and a 50/50 shot, that is 11.5 g of shot and 9.2 g of base. The shot fills half the bottle here, which is why a high strength recipe leaves so little room for base. A 70VG/30PG shot is denser, at about 1.19 g/ml, so the same 10 ml weighs 11.9 g.

Recipe 2, 50 ml at 4 mg/ml

The same single shot in 50 ml gives 20 × 10 ÷ 50 = 4 mg/ml, or 3.6 mg/ml with an 18 mg/ml shot. With 10 % concentrate (5 ml), the base rises to 50 − 10 − 5 = 35 ml, which is 11.5 g of shot and 40.25 g of base on the scale.

The same 20 mg/ml shot therefore produces a 10 mg/ml or a 4 mg/ml liquid depending on how much it has to cover, and an 18 mg/ml shot gives 9 or 3.6 mg/ml. The weighing routine behind these recipes is set out in our guide to setting up a DIY e-liquid workstation.

Salts or freebase, what changes for the mixer

Both share the bottle size, the 20 mg/ml ceiling and the maths. The difference lies in the chemical form of the nicotine and in how it feels.

In a salt shot, the nicotine is paired with an organic acid, which lowers the pH of the solution. UK product pages often name it, Make My Vape listing its nicotine base as salicylate and DarkStar mentioning salicylic acid.

At the same strength, the throat hit is softer than with freebase nicotine. That is what makes the strengths of recipe 1 workable in a tight draw pod, where a freebase shot at the same level quickly turns harsh.

For the mixer, the consequence is simple. The maths does not change, but the strength you choose may. Do not swap a freebase shot for a salt shot at the same strength without testing the result on a small volume first.

Getting an even mix

A shot that has been poured is not a shot that has been mixed. Until the liquid is uniform, the bottom of the bottle can hold more nicotine than the top, and the first refill will not match the last.

Order helps. The shot goes into the empty bottle first, followed by the concentrate and then the base, which carries everything along as it falls. The bottle is then capped and shaken hard for one to two minutes, turning it over several times.

A visual check completes the job. Held up to the light, a mix that is still uneven shows wavy streaks, caused by the different refractive indices of PG and VG. While they are visible, keep shaking. With a 30/70 or max VG base, which is thicker, this stage takes noticeably longer.

Storing an opened shot and the finished mix

A capped shot goes back into its original packaging, cap screwed down, inside a closed box kept high up or locked away, apart from food, light and heat. Gloves stay on until it has been put away.

Nicotine oxidises in contact with air, and a shot that darkens over time is the visible sign. Write the opening date on the label and use opened bottles first. The finished mix gets its own label too, with the final strength, the words “nicotine salts” and the date.

Why a DIY recipe always stays under the ceiling

Under the 2016 regulations, nicotine-containing liquid is limited to 20 mg/ml, refill bottles to 10 ml and tanks to 2 ml, while separate rules bar the sale of nicotine vaping products to anyone under 18. A 20 mg/ml salt shot sits at those ceilings, and a DIY recipe can only dilute it.

The 20 mg/ml on the label is a maximum, not a target. No part of the process should aim to go beyond it, whether by cutting the base or by looking for stronger nicotine outside the regulated market. The maths exists to reach a strength you have chosen below that ceiling, and to check it.

FAQ

These are the practical questions that come up once both recipes are in hand.

Do salt shots need a special base?

No. The base is chosen for your device and your concentrate. You simply need to count the shot’s own ratio in the final mix, since it fills part of the bottle.

How many shots do I need for a litre at 3 mg/ml?

With 20 mg/ml shots, 3 × 1,000 ÷ 20 = 150 ml, which is 15 bottles. With 18 mg/ml shots, 3 × 1,000 ÷ 18 comes to about 167 ml, so 17 bottles with a little left over.

Is a salt shot weighed like a freebase shot?

Yes. Its density depends mainly on its PG/VG base, not on the form of the nicotine. A 50/50 shot weighs about 1.15 g/ml, the same as a 50/50 base.

Why does a flavoured mix always stay below 20 mg/ml?

Because the concentrate dilutes the shot as soon as it goes into the bottle. With 10 % concentrate and 20 mg/ml shots, the highest possible strength falls to 18 mg/ml.

What should go in the log for a salt recipe?

The nicotine type, the shot’s strength and ratio, its batch number and opening date, then the final strength as calculated and checked. That is everything you need to repeat the recipe exactly.

Nic salt shot in DIY, one formula and three habits

One formula, target strength times final volume divided by shot strength, plus its reverse check. Then three habits, pour the shot first, shake until the streaks disappear, and put the bottle away after the last weighing. The nic salt shot then takes its proper place in the recipe, at a strength you have chosen and verified.

From the same recipe book

Editorial guide for adult readers only. Vaping products usually contain nicotine, which is addictive, and nicotine vaping products are not for sale to anyone under 18 in the UK. This guide describes a mixing method and is not a buying recommendation.