I think you will find that that is not the "recommended range" as intended by the code. 

http://www.hobartbrothers.com/pdf/datasheets/Excel_Arc71.pdf

The Hobart data sheet provides a range from 170-260 Amps (provided 100%Co2)

You are using an all position electrode, you may produce an all position WPS that covers a wider range of current values.

The reason the suggested amperages for vertical welds are lower is simply because it won't run well at a higher range......  I don't see why you couldn't run flat and horizontal welds in the lower recommended ranges (at slower travel speeds).

The maximum Wire feed speeds (500ipm/260 amps) Hobart recommends are designed for maximum production speeds and thicker materials, but might not be suitable for 1/8 fillets eh?

For training purposes I usually suggest learners use the lower ranges for their first guided bend tests in order to have a little more "think time",  It takes a bit of experience to run FCAW at 500ipm.

I think the whole range may apply.

There is no reason not to allow the welder to use the lower amperage as a "test" sample. If the sample passes the bend tests, you have established a more usable range and you can revise the WPS if it makes sense. You need to include information on the electrode extension and voltage as well.

Amperage is a poor way of monitoring any of the semi-automatic welding processes. There are three "constants" that should be listed on the WPS. I call them "constants" because with most conventional CV power supplies they do not change whether the welder is actually welding or if he is simply holding the gun in the air and spooling off wire. The three constants are:

Voltage,
Wire Feed Speed, and
Electrode Extension

Once the values of the three constants are "set", the amperage is determined by the power supply, i.e., the amperage determines the melt-off rate, thus the voltage (arc length) is maintained. The amperage is a variable that will change with any change in the electrode extension, i.e., lengthen the electrode extension and the current will decay, shorten the electrode extension and the current will increase.

Many of the problems I've encountered in the shop were a result of the welders not understanding the need to control the electrode extension. They would set their voltage (arc length) and adjust their current to get a smooth burn, with no regard for the electrode extension. After a break, they would complain the machine wasn't running right; "it's too cold" or "it's too hot". In reality, they had changed their electrode extension without being cognizant of the implications or the affects on the welding operation.

Now, back to my opening statement, one of the reasons we use formal WPSs is to obtain more consistency in production. That is, when all the welders follow a WPS that lists narrow ranges for the welding parameters, the end result will be more consistent welds from one welder to the next and with more predictable results. I like to see manufacturers qualify their welding procedures and base their production WPSs on the parameters used to qualify the procedure and subsequent welder qualification tests so that the production WPS can be based on "lessons learned" during the qualification process and "real" useable welding parameters.

Someone is bound to start hollering that the welder must work within the specified parameters on the WPS. So true! However, there is nothing saying that you can't use a separate WPS with broad ranges to qualify the welders and a separate WPS for production welding that lists more restrictive parameters.

One reason to monitor and record the actual welding parameters used by the welders when they take their performance qualification tests is to compile a reasonable data base of the welding parameters that produce acceptable results and those that do not. As the "welding engineer" or "welding technician" you can "bracket in" on the parameters that produce the desired results, i.e., tighten up on the welding parameters listed on the production WPS.

I do not advocate wide ranges for the voltage, wire feed speed, and travel speed when developing a WPS for a specific application. Once again, narrow ranges will result in more consistent welds from one welder to the next. However, there are cases where the WPS is developed for "general welding" that involves thin and thick materials, various welding positions, groove and fillet welds, etc. that necessitates the need to list wide ranges for the welding parameters. However, listing wide ranges for the welding parameters will result in inconsistency of weld appearance from one welder to the next.

You refer to tables from section 3 and well as section 4. Remember, section 3 deals with prequalified welding procedures where you abide by all the requirements of prequalification. Section 4 is for those welding procedures that deviate from the conditions of prequalification and are required to be qualified by testing. Two reason for qualifying a procedure by testing are the lack of industry recognized satisfactory use and a history of successful results. So, WPSs qualified by testing are restricted to what has been proven to work by the testing regiment.