Manual / Guns and Loads

Guns and Loads

A solver is only as honest as what you feed it. This is every field in the rifle and load editor — what the number is, where to get it, and exactly what it changes in your firing solution. Fill in the four rifle chips and one load properly and the rest of the app has what it needs.

Rifle first

Sight height, zero range, twist rate, barrel length. Set once, good for every load.

Then the ammo

Bullet weight, muzzle velocity, BC and its model. Scan the box to skip the typing.

Both devices

Create and edit on iPhone or on the watch alone. It syncs either way.

Wrist Dope Guns list on iPhone showing five rifles, each with four status chips for sight height, twist rate, barrel length and scope units

The GUNS page. Green chips are set, an orange “Set ›” chip is missing, a dashed chip is still the default.

Start here

A rifle, and the loads you shoot through it

Wrist Dope splits your profile in two. The rifle holds everything that stays put when you change ammunition — the optic's height over the bore, where it's zeroed, the barrel. Each load under it holds the bullet: weight, velocity, drag.

Every rifle row carries four chips. They are a checklist, not decoration:

Green — you set this value.
Orange “Set ›” — nothing stored. Tap it to open the editor on that field.
Dashed outline — sight height is still exactly 2 in, the value the solver falls back to. Worth confirming against your actual rings.

Free covers three rifle-and-load combinations. Past that, extra loads are kept and shown locked rather than deleted, and the one-time Pro upgrade unlocks them all.

Edit Gun sheet on iPhone with Identity, Geometry and Units and Display sections

Edit Gun. The ⓘ next to sight height, twist rate and barrel length explains how to measure each one.

The rifle

Every field, and what it moves

Add Gun on the GUNS page, or tap a rifle and then Edit Gun.

Name

Where to get it — Whatever you call it out loud.

Display only. Nothing in the solve reads it, so name it for the safe, not the cartridge — you may end up with two rifles in the same chambering.

Cartridge

Where to get it — Stamped on the barrel; it’s also on the ammo box.

Picking one fills in bullet diameter for you and tells the load editor which factory ammunition to offer. Pick an airgun caliber on a new rifle and the app also seeds airgun-sized defaults for the zero and the range card.

Bullet Ø

Where to get it — Filled in by the cartridge. Override it only for a wildcat or an odd bore.

Used directly by the solver, and combined with bullet weight to estimate the bullet's length — which is what spin drift, stability and aerodynamic jump are computed from. A wrong diameter quietly distorts all three.

Sight Height

Where to get it — Bore centreline to scope centreline, straight up. Typically 1.5–2.0 in on a bolt gun, about 2.6 in on an AR with a flat-top mount.

It tilts the whole sight line relative to the bore, so it changes every hold past the zero. Solving the same 6.5 Creedmoor load twice — once at 1.5 in, once at 2.6 in, both zeroed at 100 yards — moves the 600-yard come-up by 0.26 mil, about 5.5 inches on target. Leave it unset and the solver uses 2 in, which is why the chip goes dashed at exactly that value.

Zero Range

Where to get it — The distance you actually sighted in at.

This is the reference every hold is measured from, so an error here is an error at every distance at once. Move that same load from a 100-yard zero to a 200-yard zero and every come-up on the card shifts by 0.47 mil — 300 yards, 600, 1,000, all of them. It also sets the distance your group size is read at.

Twist Rate

Where to get it — Stamped on the barrel near the chamber or muzzle. 1:8, 1-8 and 1/8 all mean the same thing.

Without it the solver has no rotation to work from, so spin drift and aerodynamic jump are not applied at all — the editor says so under the field. For a 140 gr 6.5 out of a 1:8 barrel that is 0.21 mil of spin drift left on the table at 1,000 yards, about 7.5 inches. Twist also drives the stability check: if a load on this rifle won't stabilise at the twist you typed, a warning appears in the editor while you type.

Barrel Length

Where to get it — Bolt face to muzzle crown, action closed and the rifle unloaded. Don't count a brake or a suppressor.

Box velocities come from the ammunition maker's test barrel, not yours. Give Wrist Dope your length and it estimates what that load should actually leave your muzzle at, and marks the number as an estimate. Change the barrel length later and every estimated load on the rifle is re-estimated to follow it.

Angular

Where to get it — However your scope turret is marked.

MIL or MOA, per rifle — two rifles can disagree. Distance and velocity units are global and live in Settings, not here.

Show Velocity/Energy

Where to get it — Your call.

Adds remaining velocity and energy columns to this rifle's range card. It changes nothing about the solve.

Edit Load sheet on iPhone showing Active Load and Zero Reference badges, Identity, Ballistics and Consistency sections

Edit Load. Bullet weight, muzzle velocity, BC and BC model are the four numbers the trajectory is built from.

The load

Bullet, velocity, drag

Add Load from a rifle's page. On a new load, Start From offers published factory ammunition in that cartridge, and Choose Bullet… offers component bullets at that bore — either one fills the ballistics in for you.

Name

Where to get it — Whatever’s on the box, or your load book.

Display only, but it's what you'll pick between under time pressure. Include the bullet weight.

Bullet Weight

Where to get it — On the box, in grains.

Feeds the trajectory directly, and with bullet diameter it sets the estimated bullet length behind spin drift and stability.

Muzzle Velocity

Where to get it — Chronograph it if you can. Otherwise the box number, adjusted for your barrel.

The single most punishing field on this page. A box number 100 fps optimistic puts a 6.5 Creedmoor 0.77 mil off at 1,000 yards — 28 inches, a clean miss on most targets. On an existing load the row opens a sheet instead of a keypad, so the number always carries a source with it.

BC and BC Model

Where to get it — Published by the bullet maker. Match the model to the number you copied.

The BC only means something alongside its drag model, and the two are not interchangeable. Typing a G1 figure of 0.620 while the model is left on G7 throws the 1,000-yard hold out by 2.0 mil — roughly six feet. If the maker publishes both, prefer the G7 pair for a modern boat-tail bullet.

Group Size

Where to get it — The extreme spread of a 5-shot group, measured at this rifle’s zero range.

Not a universal 100 yards — the app reads it at the distance you sighted in at, so an airgunner's 0.4 in at 25 yards is treated as the 25-yard group it is. Tap the unit chip on the row to type it as an angle instead. Feeds the hit percentage.

Velocity SD

Where to get it — Your chronograph’s standard deviation over a string.

Wrist Dope solves the shot a second time at your velocity plus one SD and uses the vertical difference as the round-to-round spread. It only changes a displayed number once you've set a target size on the FIELD page, which is what turns hit percentage on.

Factory Load and Manufacturer

Where to get it — The box. Off means a handload.

Turning it on relabels the velocity field as a published value and lets you record the maker. Scanned loads arrive with both already filled in.

A rifle's load list on iPhone showing three loads, one marked active with an orange checkmark and a green ZERO badge

Tap a rifle to see its loads. The orange check is the active load; the green ZERO badge is the zero reference.

Zero

Active load, and the one your scope is zeroed for

Two different marks live on a load, and mixing them up is the most common way to get good numbers from bad dope:

Active — the load your dope is being solved for right now. One across the whole app.
Zero Reference — the load your scope is physically zeroed with. One per rifle.

Every other load on that rifle takes its zero from the reference, so you don't re-zero to swap ammunition. If a second load prints high or low of the reference at the zero distance, record that distance as its zero offset and the app converts it to an angular correction on every hold. On iPhone the offset lives on the load's Field Trueing card; on the watch it's a row in the load editor.

A load's detail page on iPhone showing the rifle chips, the bullet, and a velocity ladder with chronograph, trued, manual, estimated and published rows

The load page. The ladder lists every velocity the app knows for this load and ticks the one in use.

Provenance

Where the velocity came from

Tap a load and the velocity section answers “where did this number come from?” on its own. Five rungs, highest wins:

Trued with chronograph — you measured it over a chronograph.
Trued on target — the app solved it back out of real impacts at distance.
Manual entry — you typed it.
Estimated — the published number adjusted for your barrel length. Marked with an asterisk everywhere it appears.
Published value — straight off the box, from someone else's test barrel.

Nothing here is silent. An estimate never passes itself off as a measurement, and the rungs you aren't using keep their numbers so you can see what you gained. Measuring a velocity properly is its own job — the Field Trueing card at the bottom of the load page walks you through it, and the BC gets the same treatment once the velocity is trustworthy.

Scan result on iPhone reading Gun and load ready, with cartridge, load, manufacturer, bullet weight, muzzle velocity and G7 BC filled in

Scan Ammo reads the UPC and builds the rifle and the load, published ballistics already filled in.

Shortcut

Scan the box instead

Scan Ammo sits at the top of the GUNS page and on each rifle's page. Point it at the barcode on a box of factory ammunition and it fills in cartridge, bullet weight, published muzzle velocity and BC, and tags the load with its maker.

From the GUNS page it can create the rifle too, then hand you straight to Live Fire.
From inside a rifle it adds the load there. Scanning the same box again recognises it rather than duplicating it.
The first release of the catalog covers Hornady Match factory ammo, with more brands coming. Anything it doesn't know says so and you enter it by hand.

A scanned load still carries a published velocity from someone else's test barrel. Give the rifle a barrel length, or true it, before you trust it at distance.

Wrist Dope New Gun editor on Apple Watch showing Gun Name, Cartridge and Sight Height rows

The watch GUNS page creates and edits rifles and loads on its own. The Crown drives every number.

On the wrist

Build a rifle without your phone

Swipe to the GUNS page on the watch and you can add a rifle, add a load, edit either, and switch which load is active — no phone in the equation. Each number opens a Crown input: turn for coarse steps, tap the buttons for fine ones.

Two things are deliberately phone-side. Barrel length is set on iPhone. And a velocity that came from a chronograph or from trueing shows as locked with its source underneath and Change on iPhone below it, so a stray Crown turn can't throw away a measurement you paid for in range time.

Everything you enter on either device syncs to the other.

Duplicating, deleting, backing up

Duplicate a rifle — press and hold its row on the GUNS page. You get a copy with all of its loads, which is the fast way to log the same rifle with a different optic.
Delete — deleting a rifle deletes every load under it, on your phone and your watch. The app asks first, and it can't be undone.
Back it up — Export Guns at the bottom of the GUNS page writes one file with every rifle and load, and Import Guns reads it back. The same file imports into the Android app, so it doubles as the way to move between platforms. Export before a phone swap.

Numbers don't look right?

The BC model doesn't match the BC. A G1 number sitting in a load set to G7 is the biggest silent error on this page — thousands of an inch of typing, feet of miss at distance. Check the bullet maker's page and match the pair.
The velocity is still the box number. Open the load and read the ladder. If it says Published value, that speed came from a test barrel that isn't yours. Add a barrel length for an estimate, or true it.
Zero range is wrong. It shifts every hold by the same amount, which reads as “the app is off by a constant”. Confirm it matches where you actually sighted in.
Sight height is still the default. A dashed chip on the GUNS page means 2 in — the fallback, not a measurement. Tall rings and an AR mount are both well off it.
Wind holds ignore spin drift. No twist rate means no spin drift and no aerodynamic jump. The chip reads Set › until you fill it in.
A load you can see won't solve. Free keeps three rifle-and-load combinations usable. Extras stay on the device, shown locked, and the one-time Pro upgrade opens them back up.

One honest caveat: good inputs make a good prediction, not a guarantee. Verify your data on paper at distance before you need it, and shoot safely, responsibly and within the law.

Still stuck? support@wristdope.com