[paulca]

I agree with others, the car is telling you something. It's saying "Don't put me into 1st yet!". I would listen to it.

You can stop in any gear, there is on need to rally shift down the box, it's not a sequential. Block shifts are fine. 6th can be a bit difficult to stop in as you would need to clutch down at 25mph to prevent under reving. So an intermediate downshift to 3rd or 4th is wise.

The term some instructors here us is, "Gears to go, brakes to slow".

Of course this changes if you are "hooning it". I selected first for a hairpin bend the other day at about 20mph while deep on the brakes. A little throttle blip and then 'listen' to the synchro and what it's telling you, ie. don't force it! Push it against the synchro lightly, it will resist a little until it's ready then it will pop in.

You have to consider the shafts in the gearbox, if you are making a big rev change. If you were in 4th at 20mph, then your engine and gearbox speed would be low, around 1k. You then clutch it disconnecting the engine from the transmission and pull it out of gear. Now a large portion of the gearbox is spinning idle, connected to nothing. It is still spinning for 1k rpm (and slowing). You try and select 1st. The synchro has to spin that idling shaft up to road speed for 1st which at 20mph is about 5k. The shafts are not that heavy, but the synchros are small, so you have to give it time. Forcing it will make it grind.

The same happens the other way around if you red line it in 2nd and then (as that brings you to the speed limit here) select 6th to cruise. Engine speed 7.4k, required RPM for 6th at 60mph, 2k. So you are asking the synchro to synchronize a shaft at an equivalent 7.4k rpm with a shaft at an equivalent 2k rpm. You need to be patient with it. Hold it lightly against the synchro, don't force it, it will select when ready.