The owner of an alleged pirate vessel sought last weekend by the Coast Guard said today that his crew did indeed brandish a firearm and a skull-and-crossbones flag, but only to frighten off three men they thought might be drug smugglers intent on scuttling or capturing their vessel.

Ricks Savage, of Berlin, Md., said he was not aboard his boat, the Sarah C. Conway, Saturday when his crew ordered away divers hired to investigate a sunken wreck some 30 miles out in the Atlantic. But he confirmed that his crew was attempting to remove items from the wreck even though the ship has not yet been officially declared abandoned and thus fair game to salvagers.

"My son told me they the divers came up out of nowhere in a little white boat with no markings and tried to come aboard," Savage said in a telephone interview. "They didn't say who they were or anything."

At that point, he said, his son brought out "a .22 rifle" in order to frighten off the strangers.

"There's too damn much stuff going on offshore with drugs these days to buy allow anything like that," explained Savage, a Chincoteague, Va.-born ice-plant owner. "You don't let anybody on your boat like that. My daddy made that very clear to me 30 years ago."

The wreck is the collier Marine Electric, which foundered in a gale last Feb. 12 with a loss of 31 lives some 30 miles offshore Chincoteague. It was owned and operated by Marine Transport Lines Inc., of New York.

Savage said that his crew was conducting its salvage operations in accordance with the philosophy long embraced by Eastern Shore watermen of free plunder beneath the sea.

"We've been picking at wrecks for years," he said. "I know at least four other boats, some of them from Norfolk, have been out on this one as well."

The confrontation Saturday took place when Jeremiah Shastid, 32, and his brother Roy, both of Waldorf, Md., and one other diver, all hired by attorneys for families of the deceased crewmen, arrived in the area to continue their survey of the wreck's shattered hull.

Shastid, who said that both he and his brother served in the Marines and recognized heavy weapons, insisted today that the rifles they saw resembled M16s.

"I know an M16 when I see one," he said. "Two of them the weapons had bipods on the barrels. The third was some kind of weapon with a scope."

He said the Coast Guard, which Tuesday called off its investigation into the matter, had urged him to press assault charges against the Sarah C. Conway crew but that he ultimately declined. "It wasn't really an assault," he said. "They didn't point anything at us. I merely told the Coast Guard because I want them to know what's going on.

"I'm going back out there and, if this happens again, I'm gonna call them," Shastid said. "And I don't want to have to answer 100 questions over the radio while I'm looking down the barrel of a gun."

For his part, Savage maintained that the incident "has been way overblown."

He said his son, concerned for the safety of the 111-year-old clamming vessel, brought out a rifle after Shastid tried to come aboard.

"That, obviously, never should have happened," he added.

He said the automatic weapons described in Shastid's report to the Coast Guard were "somebody's imagination."

No such weapons are carried on the Sarah C., he said, though he added he could not say what individual crewmen might have brought aboard.

At Chincoteague, meanwhile, Shastid, who is being paid $700 a day for his underwater work, prepared today to return to the wreck site and dive again, even though he will now have to dive alone--30 miles at sea in the eerie darkness of 120-foot depths--since the third member of his team quit after the incident, leaving only his brother to remain above, as safe diving practice dictates.

His work on the Marine Electric is very important to him, Shastid said, because it is the first major commercial venture for his own company after careers that have ranged from deputy sheriff to go-go dancer. An Anacostia native, whose beefy good looks carried him to Playgirl magazine's centerfold in December 1975, he is anxious to prove his is not just another pretty face.

The wreck of the Marine Electric is proof enough. Twice as long as a football field, her hull taller than a six-story building, the ship lies capsized and broken into two or three jagged pieces, he said, on the sands of the Continental Shelf.

The forward section--stretched nearly double its former length by shipyard surgery in 1962--appears more to have been twisted apart from the stern by the force of the wind and waves the night she sank than to have been broken off. Underwater color slides taken by Shastid show her heavy steel plating torn and twisted like the shards of a beer can wrung in two.

Shastid's most startling find so far, he said, has been that the combined length of the two sections he has found on the ocean's floor measures more than 100 feet shorter than the ship's listed 605-foot length.

"That's a lot of missing ship," he said. "And we don't know where or why it's gone."

But soon, weather permitting, Shastid will descend for the most difficult part of his mission. In the dim blue light of 20 fathoms, where visibility varies from 25 feet to four inches, he will swim through a two-foot space beneath the capsized ship and into the hull where there is no light at all.

While tidal surges suck in and out of the hatches, causing manila hawsers as thick as a man to wave "around down there like spaghetti," he will make his way nearly 200 feet down passageways and through cargo holds laced with coils of cable that could entangle him forever.

If all goes well, he will find the anchor chain locker in the bow and photograph a safety door that survivors of the wreck have told him was frozen open, allowing the sea to pour into the ship unchecked.

At stake--for the lawyers and crew survivors--is more than $100 million in negligence claims against Marine Transport, plus what one lawyer in the case contends could amount to millions more in punitive damages if a court finds the company knowingly shipped an unsafe vessel.

Shastid said he believes his work is important and the "upcoming penetration" of the hull most important at all.

"But I don't like the dark in there," he said. "I have dreams about it now."

But if he makes it--and at 6-3, 210-pounds he expects to--he will go back one final time: to look for the bodies of three men trapped in the engine room when the ship went down.

"I promised one of the survivors I'd do it," he said. "She sank so fast they never had a chance."