SLORMGORM kicks off the week…
Good solid Monday morning puzzle from this reliable setter. A few things were new to me (mountain and bird in 20a and 16d), but gettable nonetheless.
Thanks SLORMGORM!

ACROSS
1. Book tough footballer (8)
HARDBACK
HARD (tough) + BACK (footballer)
5. A table on the Titanic? (6)
ABOARD
10. A mariner caught in storm (7)
ASSAULT
"a salt" = ASSAULT (a mariner, "caught")
11. Truthfulness is really not fruitful in the end (7)
HONESTY
HONEST[l]Y (really, not [fruitfu]L (in the end))
12. One cuts people off in late on-air broadcast (9)
ALIENATOR
(LATE ON AIR)* (*broadcast)
13. Old lady giving away million is something else (5)
OTHER
[m]OTHER (old lady, giving away M (million))
15. Henry & Son Labourers (5)
HANDS
H (Henry) + AND (&) +S (son)
16. Serve as soldier… one into his guns will do this, we hear (4,4)
BEAR ARMS
"bare arms" = BEAR ARMS (one into his guns will do this, "we hear")
19. What I’d do for The Platter’s costume party is also what The Drifters might do! (2,6)
GO ASTRAY
GO AS TRAY (what I'd do for the platter's costume party)
20. Mountain discovered in planetology (5)
ANETO
[pl]ANETO[logy] (discovered in)
21. Vacuous heads will detain everyone student digs (5)
HALLS
H[ead]S will detain ALL (everyone)
23. Chilled criminal robs banks ultimately without issue (9)
CHILDLESS
(CHILLED)* (*criminal) + [rob]S [bank]S (ultimately)
25. They cover crash sites or nuptials where bishop knocks out wife (7)
BEDDING
WEDDING (nuptials, where B (bishop) knocks off W (wife))
27. Seed I got near Aldi to invigorate anaemic starters (7)
IGNATIA
I G[]ot] N[ear] A[ldi] T[o] I[nvigorate] A[naemic] (starters)
28. Dutch film about grasping local is in the can (6)
TINNED
(D (Dutch) + ET (film))< (<about) grasping INN (local)
29. Old country’s colonial name is awful, so I heard (8)
RHODESIA
(SO I HEARD)* (*is awful)
DOWN
1. Principal with long excuse to avoid relations? (8)
HEADACHE
HEAD (principal) with ACHE (long)
2. Full-of-themself type changing dollars in US (7,4)
RUSSIAN DOLL
(DOLLARS IN US)* (*changing)
3. American prudes seen in titillating Hooters (9)
BLUENOSES
BLUE (titillating) + NOSES (hooters)
4. Manage clubs with initially unmanageable winger (3,2)
CUT IT
C (clubs) with U[nmanageable] (initially) + TIT (winger)
6. Game point coming up? Got to avoid last place! (5)
BINGO
(NIB)< (point, <coming up) + GO[t] (to avoid last place)
7. Dope found in service gets male excommunicated (3)
ASS
[m]ASS (service, gets M (male) excommunicated)
8. One in utility room seen with doctor inhaling grass (5)
DRYER
DR (doctor) inhaling RYE (grass)
9. Army chap turned drug dealer (8)
PHARMACY
14. Old man in costume with hero on the move (4,7)
HOMO ERECTUS
(COSTUME with HERO)* (*on the move)
16. Noddy Holder? (8)
BIRDCAGE
Cryptic definition, noddy being a kind of bird
17. Wild group performing with XTC in commercial (9)
ABANDONED
(BAND (group) + ON (performing) with E (XTC, ecstasy)) in AD (commercial)
18. Component used in robot swan approaching land (8)
BOTSWANA
[ro]BOT SWAN A[pproaching] (component used in)
21. Sailor in the grip of heroin and sex addiction (5)
HABIT
AB (sailor) in the grip of (H (heroin) and IT (sex))
22. Standard request for people about to be shot? (5)
SMILE
Cryptic definition, as in having a photograph taken
24. Teacher one upset with bit of harsh language (5)
IRISH
(SIR (teacher) + I (one))< (<upset) with H[arsh] (bit of)
26. Mostly accomplished academic (3)
DON
DON[e] (accomplished, mostly)
More unknowns than usual with this setter — BLUENOSE, ANETO, IGNATIA, XTC & noddy. I still don’t understand how BEAR ARMS works.
No particular favourites today. Mostly enjoyable.
After too hard on Friday and too easy on Saturday I thought this was a solid challenge where the obscurities were gettable and plenty to amuse. Liked homo erectus. Thx both.
Geoff @1 I think
Serve as soldier = bear arms
Gun nuts like to uncover, or bare their arms.
Alternatively I wonder if ‘one into his guns’ means a weightlifter, and the clue refers to their habit of showing off their big biceps, or ‘guns’, by wearing t shirts.
Ie a cryptic definition.
This was fun, not too hard although I found it a bit trickier than normal with SLORMGORM to tune in to his thinking.
I enjoyed Pharmacy, Russian Doll, Rhodesia and Botswana.
I agree that Bear Arms puns on Guns as biceps.
Thanks to SLORMGORM and Teacow.
Thanks for the explanations of BEAR ARMS which had me mystified. I might have encountered that use of ‘guns’ in a puzzle but not, to my recollection, in real world. Yes, quite a few unknown words but all were gettable from the wordplay. RUSSIAN DOLL was my LOI: I had the anagram fodder and all the crossers so it should have been a simple job but that splendidly cryptic definition threw me right off the scent.
BOTSWANA, PHARMACY, SMILE, ASSAULT and ABOARD were my other big ticks. Taking L from HONESTLY to get HONESTY felt a tad same-sidey but that’s the smallest of quibbles.
Thanks both
Thanks Slormgorm and Teacow
11ac: I agree with PM@5 on this, especially as honesty could be defined as a type of plant, which would have made for quite a nice surface. Perhaps Slormgorm simply did not know this, in which case I have no complaint, or perhaps he wrote a clue based on the type of plant, and it was thought to be too obscure a meaning for this puzzle.
A nice steady workout with a few checks in reference books needed – such as for ANETO and IGNATIA. Plenty to like, HEADACHE, RUSSIAN DOLL, PHARMACY and BIRDCAGE among them.
Thanks, Slormgorm and Teacow.
I laughed out loud at GO AS TRAY.
As so often with this setter, plenty of sex, drugs, and rock’n’roll. Which, in my opinion, adds rather than detracts. Do they have Hooters (restaurant chain with busty waitresses) in Britain? If not, I think that’s what’s going on with the surface reading in the BLUENOSES clue.
Steady solve and very enjoyable. Thank you.