Best sealant for large volume tyres?

[Bolt]

I've had a few punctures on 35mm - 50mm lightweight tyres that have struggled to self seal using both Stans and Magic Milk.  The puncture holes weren't actually that big, certainly not big enough to fit a plus without enlarging the hole which I'm reluctant to do.  I'm running the 35mm tyres at ~60psi and the larger tyres at ~40.  On most occasions they do self seal but only when most of the pressure has been lost, they then hold pressure when reinflated off the bike, but as soon as I'm riding again the problem repeats again. 

[Nightmare-1]

An Innertube!

[Bolt]

An Innertube!

already fitted front and rear pending further advice

[Deano]

I found Stans worked really well on 3" tyres...

More usefully, this stuff seems a bit thicker, and worked on a tricky tyre/rim combo: https://www.ebay.co.uk/p/20033702757?iid=332357783109

[sojournermike]

Orange Seal or Orange Seal Endurance?

[BrundonBianchi]

Stans race sealant. The one with the red cap. It’s got twice the concentration of sealant thingys in it, than the other version of Stans, and seals a 38mm tyre really well IME.

[Bolt]

Thanks for the suggestions which got me to thinking why do sealant manufacturers sell more that one type of sealant (OKO manufacturers of Magic Milk have 4!)... which then reminded me of my own findings when I started out with tubeless, which was you may need a less viscous sealant to seal a less than perfect tyre rim combination but I'd forgotten that the thinner sealants may then struggle to seal larger punctures.  Interestingly OKO do offer guidance along these lines on their website:

OKO Puncture Free is a water-based liquid that is able to work on both tubed and full UST tubeless tyres.
It gives peace of mind and lasting security for the tyre’s life, with a dose of 60-100ml per tyre in mainstream bikes, depending on size.
An all-purpose product for commuting to weekend mountain biking, it is ideal to use when converting to full UST tubeless, where you need a sealant that can deal with serious punctures.   Many other bike sealants are just too weak to get the job done.
(For ‘tubeless ready’ tyres, use a rim strip plus OKO Magic Milk™)my edit... and expect an occasional puncture that does seal

[morbihan]

Orange seal endurance and plenty of it for our RH tires. We have had issues and problems using other brands to varying degrees.
They are pinickerty in large part, I suspect, because the side walls of RH tires are very thin (the appeal is the ride quality) so it may be that thicker walled high volume tires are just fine with other sealants.

[Bolt]

Orange seal endurance and plenty of it for our RH tires.

RH tyres?  As much as I've racked my brains I can't work out the abbreviation?

[LittleWheelsandBig]

Rene Herse = Compass = Panaracer-made private label tyres.

[BrundonBianchi]

Thanks for the suggestions which got me to thinking why do sealant manufacturers sell more that one type of sealant (OKO manufacturers of Magic Milk have 4!)... which then reminded me of my own findings when I started out with tubeless, which was you may need a less viscous sealant to seal a less than perfect tyre rim combination but I'd forgotten that the thinner sealants may then struggle to seal larger punctures.  Interestingly OKO do offer guidance along these lines on their website:

OKO Puncture Free is a water-based liquid that is able to work on both tubed and full UST tubeless tyres.
It gives peace of mind and lasting security for the tyre’s life, with a dose of 60-100ml per tyre in mainstream bikes, depending on size.
An all-purpose product for commuting to weekend mountain biking, it is ideal to use when converting to full UST tubeless, where you need a sealant that can deal with serious punctures.   Many other bike sealants are just too weak to get the job done.
(For ‘tubeless ready’ tyres, use a rim strip plus OKO Magic Milk™)my edit... and expect an occasional puncture that does seal

In the case of Stans, the red cap ‘race sealant’ has double the concentration of sealant crystals of the other version, and it really is noticeable, from my personal experience.

[zigzag]

In the case of Stans, the red cap ‘race sealant’ has double the concentration of sealant crystals of the other version, and it really is noticeable, from my personal experience.

can it still be injected/topped up through the presta valve?

[Torslanda]

Tannus armour?

[Bolt]

So I spent some time today taking a closer look at the tyres that had failed. The semi-slick mtb tyre had what turned out to be a pretty large hole in it which I repaired with a Rema 3mm plug patch. There were plenty of other smaller punctures which had sealed so on reflection the magic milk hadn't been doing such a bad job. 
And then on the 35mm G-One I found 10 small punctures and 4 medium but none of them that warranted plugging. Looking back there wasn't a lot of sealant in the tyre when the last puncture failed to seal and a fresh top up of Magic Milk seems to have fixed the problem.