See this post by TTBit where he describes how he is doing something similar with DYM, pre-1965 silver US dimes.

Personally I think the negatives of trying to use one specific type of ammo as currency outweigh any benefit. Rather I'd think you'd just sell all your various types of ammo priced in whatever currencies make sense for you to accept; you'd then use Ripple to allow people to pay you that currency using whatever currencies/credit they have on Ripple (the same way you'd use Paypal as a merchant).

If you did want to do it anyway ...  [The following may seem complicated but if you replace "9MM via Ripple" with "USD via Paypal" it's the same level of complexity for what Paypal lets you do. Ripple lets you do more however and with less fees.] ...

You'd post somewhere (on the store website, here, where ever) what your redemption policy on "9MM" is (as you say above: in store or shipped; probably add that amounts need to be above a minimum and rounded off to whatever the ammo box size is, e.g. multiples of 24 or 50 or whatever, or make the unit "boxes of 9mm" rather than "rounds of 9mm"). This would act kind of like a gift card.

If someone sends you cash or pre-orders in-store a years supply of ammo you could directly send then "9MM" (via Ripple's "Send" interface). However if someone sends you cash they likely want you to send them the ammo and not IOUs; unless they want to trade or resell them or something. Again, this use would be kind of like a gift card.

If you want to directly accept currencies/IOUs traded/used on Ripple you can enter trade offers. For example, on the trading interface type in "9MM/BTC" (you need to type it in because 9MM is not a standard currency type). You select your ripple address as the 9MM issuer and you'd select some gateway as the BTC issuer (e.g. Bitstamp; you could enter multiple offers for multiple BTC issuers, perhaps even yourself) and enter in a SELL order at X rounds priced at Y BTC per round. [Since Y would probably be very small you'd likely flip this around and instead enter a BUY order for BTC/9MM for 1/Y rounds per BTC, the effect is identical; this is why BTC/XRP is used instead of XRP/BTC].

Anyone can now try to redeem/use/pay you "9MM". Lets say they go to your gun store's web page and enter an order form asking for X rounds. You list Ripple as a payment option and if selected you send them to a link (just like paypal works). The link includes your ripple address, an identifier, the amount+currency (X 9MM; but it could be Y USD or whatever). The user then gets the Ripple send interface to send X "9MM". Ripple finds whatever paths are available to the user and either says "no path" or says something like "you could send X 9MM or Y BTC or Z USD or # XRP" the user picks whatever available currency they hold to complete the payment. If they select a non-9MM currency Ripple automatically executes the appropriate trades (perhaps some third party is SELLing 9MM for EUR, this gives the user the ability to pay in EUR). Also note that within a currency Ripple will find paths through extended credit lines without needing trades. E.g. the person can pay in EUR buy redeeming some of their IOUs with the guy trading for 9MM and by owing someone else that had EUR the remainder, the paths can be complicated but the user just sees "pay # EUR ?".

If Joe Schmoe is at the range and "borrows" a box of X rounds from Fred; then Joe could record this debt by sending Fred X "9MM" on Ripple; this would be a 9MM IOU issued by Joe. By themselves they can't do anything with this IOU. However, Joe later trades some of his BTC for your 9MM IOU. Now Fred can send you 9MM to be redeemed for actual ammo (Ripple ripples the payment through Joe basically swapping the Joe-9MM for your 9MM IOUs) thus clearing the Joe's debt.

Typical use is not as complicated as some of the examples in this topic. Once setup, you typically just tell Ripple who you want to pay, the amount/currency you want to pay, and seconds letter it's done.

Imagine trying to explain to someone unfamiliar with it how you get your paycheck from your employer and turn it into groceries. Just as many, if not more, hoops (e.g. employer pays a paycheck printing company and a bank to transfer money to your bank that pays you interest and charges you fees; you use an ATM to get cash and give cash to a grocer that deposits it in their bank; etc, etc). It's just that we're all familiar with how that works and not familiar (yet) with using Ripple.

More equivalent to Ripple would be to explain to someone how they can use Paypal to receive payments for their goods/services vs. Ripple. Ripple might have one extra step (the ripple->gateway step) but the fees can be a lot less then Paypal.

No. There is a lot wrong/confused in your post. Starting with, there is no "record kept via XRP".

If you pay someone X BTC on Ripple then balances get adjust so that your balance goes down by some amount (X BTC plus fees, Y USD via a trade offer, etc) and their balance goes up by exactly X BTC. Ripple also destroys 0.00001 XRP of your balance as a transaction fee.

If the payment goes through the Bitstamp gateway (e.g. you have none of the payee's BTC IOUs, you have no available credit in BTC with the payee, and there is no available credit in a trust line with lower fees), then they get X BTC in IOUs from Bitstamp, your balance will go down by X*1.002 BTC of Bitstamp IOUs (the extra is the 0.2% Bitstamp transfer fee that Bitstamp charges) and your balance will also go down by 0.00001 XRP, the Ripple transaction cost.

Your example had no loan. Only if the payee had previously entered a trust line to you of >X BTC would it be a "loan" and it would have been the payee "loaning" the payer (you) the amount.
In this case, the above payment of X BTC would result in the payee's balance going up by X BTC (all in your IOUs), your balance would go down by X BTC (showing up as a negative amount to the payee on the client's trust page; you'd keep any gateway or other issuer BTC IOUs you may have) and your balance would also go down by 0.00001 XRP.

The only way you get XRP is if you trade (i.e. SELL) BTC for XRP. Then it isn't a loan, it's a sale. If you later want BTC back for that XRP you'd have to make another unrelated trade offer (i.e. BUY BTC/XRP).

chriswen is running a LTC to Ripple gateway.

See https://bitcointalk.org/index.php?topic=162160.msg1706418#msg1706418
and https://bitcointalk.org/index.php?topic=155124.msg1644810#msg1644810

Sure, one way would be to set the price of your items in the currency or currencies of your choice, USD, EUR, BTC, whatever. (e.g it'd be a lot easier for an American just to price items in USD rather than always looking up the daily or hourly BTC exchange rate). Generate a QR code and/or a Ripple URI something like https://ripple.com//send?to=r3kmLJN5D28dHuH8vZNUZpMC43pEHpaocV&dt=12345&label=Invoice23&amnt=15.23/USD on your checkout webpage or invoice or whatever.

Probably trust a well known gateway like Bitstamp for the currencies you want to accept. This will help ensure Ripple will be able to find a payment path to you.

When people go to pay on you via Ripple the system will see what payment paths are available and give them the option of which of their IOUs to use. E.g. you wanted $15.23 USD and Ripple says I can use $15.468 CAD to pay you. You don't care what currencies I use or if I'm borrowing from a trust line or whatever; you just get what you asked for from one of your trusted sources.

If you're using an automated checkout you'd add a destination field in the payment request URI and wait for payment(s) and adjust the "amount due" field on your customer's page as required until you get the full amount (perhaps I want to pay you $10 USD + 1 DYM + $3.28 CAD using several payments instead of one).

When you want your funds out of Ripple you transfer them to a gateway and have them added to your bank account (or sent to you via BTC).

Those are the only ways to get value out of or into Ripple.

The same way if you want to use Paypal or Google Wallet as a payment processor you need to trust them until you get the funds in your own account, you need to trust the gateway (or your trust lines) until you can get your money out. With Paypal and Google Wallet you pay high fees and have lots of restrictions, charge backs, limited currency support, etc.

If true, collect your reward: https://ripple.com/bug-bounty/

FYI, it's not /forums but /forum and I haven't noticed any errors recently.