The Titleist 718 AP1 irons replace the 716 AP1 and continue the Advanced Performance franchise that started in 2008.

The 718 AP1 irons take the model in a new direction with the 4 and 5 iron now featuring a hollow construction rather than a large cavity back.

Titleist say that these are their most forgiving irons and this comes from the use of High Density Tungsten weights in the toe of the heads. There is now 56 grams of the stuff, up from 42 in the previous model and this works with the rest of the head construction to create a large unsupported face with weight around the edges to maximise forgiveness.

The cast 17-4 Stainless Steel hollow body has a high strength steel face insert welded on to it and the leading edge has been 'pre-worn' or ground off in order to help it move through the turf more easily.

The hollow design gives the 4 and 5 iron a different look at address with a fairly thin top line for this type of iron. The sound was different to the cavity back long irons of the 716 range, with a slightly more muted, hollow sound, but which was still pretty good.

Certainly the 5-iron in particular was excellent and during a fitting was providing more launch and distance than the 718 AP3 5-iron and would be an excellent point to blend into AP1 from another set.

The 4-iron did not feel quite as lively as the 5 or the previous cavity back 716 4-iron, but the performance was still an improvement on what went before.

There is no 3-iron now as the 4-iron is 21° and the rest of the set from 6 downwards reverts to the large cavity back design on the previous model.
The changes Titleist has made with the 718 AP1 make these a little longer by increasing the face speed and lowering the spin with lofts that are 1° stronger in the 4 to 9 iron.

Like before the head length and offset reduce as you go down the set and by the time you get to the official P wedge it looks reasonably midsize and very playable, which is unusual as sometimes in game improvement sets they can look boxy.

I say the official P wedge, as it is so strong at 43° that there is now a gap wedge at 48° and a gap gap wedge at 53° which have both given up on the letters and just have the lofts on the sole.

This highlights the industry wide issue where almost half the irons in your bag are called wedge, but at least by putting the lofts on Titleist are clarifying the situation a little.
Surely it is only a matter of time before lofts appear on all clubs, even if they are beside the existing club numbers. However if golfers continue to buy irons using a launch monitor on distance rather than accuracy and stopping power, then the arms race with lofts and numbers will continue.
Thankfully the gap and gap gap wedges continue the style and shape of the 718 AP1 irons so that you can have three cavity back wedges all the way down your set until you get to the...err...wedges. This is a good thing because it keeps the same style of cavity back head throughout the set rather than forcing you to switch to effectively bladed irons for full wedge shots from around 110 yards in.
The stock shaft is the True Temper AMT Red that is an ascending mass shaft that is lighter in the long irons and gets heavier as you move to the short irons, but there are also many other options available through Titleist custom fitting.

I was telling anyone who would listen that the 716 AP1s were not only excellent irons for mid to high handicappers, but that better players should also look out for some of the longer irons as they are very playable.

The hollow head construction helps improve this performance in the long irons and looks better than a big cavity, even if the 4-iron is not quite as sexy to hit as the previous one, but I am splitting hairs here.
The rest of the set is extremely playable by golfers of pretty much all levels, yes even single figure players. A lot of game improvement irons are managing to incorporate the feel and sound of better player irons and the 718 AP1 is a good example of this.
Anyone from high single figure upwards should be looking at a couple of AP1s for a blended set with 718 AP3, with anyone in double digits taking the whole set.

The progressive head size gives lovely shaped short irons combined with forgiving mid and long irons and the feel for this style of head is very good. With a very shiny finish it looks like a serious golfers iron, with serious defined as keen rather than good, so I hope everyone is listening again when I say that the Titleist 718 AP1 is a must try.